Haven't done much PvP over the past couple of months, but...response to your inquiry.
OK...this response is simply my preferred style and way of PvPing with a PB
which Ive been doing for 3+ years (so, even before they were good). There are many ways to approach this and be successful, so do Id recommend some play-testing and find what works best for you and what is the most fun.
***Bright Nova Form***
Let's talk about the powers and how to best slot them.
Bright Nova (the form itself). There are a few ways to look at this power. You can use it to bump up your +To Hit and get some bonuses, or you can slot it for other things like max travel speed and endurance recovery. I like to get as many set bonuses as I possibly can (especially +Acc, +Rech) so I opted to 6-slot this power with 5 enhancements from the Adjusted Targetting set (to get +Rech and + Acc) and slotted the +Perception IO in the 6th slot.
Like I said, there are pro's and con's to this type of slotting. Bright Nova flight is inherently faster than other forms of flight, but it's not fast enough to chase down someone using SS or SJ even if it was fully slotted. I opted to increase my To Hit and get the bonuses and perception offered from the previously mentioned set/IO. You could use the 6th slot for a Flight Speed IO and throw the +Perception IO into Build up. See what works best for you and go with that.
Bright Nova Blast / Bolt. I'll group these two single-target powers together because their slotting is interchangeable and should be pretty much the same. Both activate, animate and recharge really quickly. In fact, by the time your global bonuses kick in and Hasten is running, you won't have to worry about recharge in these powers.
The big 'secret' behind these two gems is that they have a natural range of 100 ft and pack quite a whallop. That's 20 ft. more than your typical blaster or defender blast. To capitalize on this fact, I encourage slotting these each with 3 Hami-O's Dmg/Rng (the name escapes me now...maybe Centrioles?). This will "cap" their damage and put you in the area of inherent "snipe" range. This allows you to hover-blast and get 3 or 4 attacks off before your opponent can get a visual on you. The other 3 slots can be devoted to your enhancement of choice. One school of thought is to slot it out with Accuracy to maximize your effect against defensive builds. Between that, your +To Hit and your -Def you'll be hitting things even using Tier 9s like Elude. However...against most opponents, a couple of Accuracy IOs are sufficient leaving you the opportunity to put a Proc in the final slot. In fact, if you have enough global Accuracy bonuses, you could throw 2 Procs in each power to go for that extra chance for damage. I am of the thought that I'd rather hit more reliably than have the bonus damage, but I've been tempted many times to put another Proc in each power. It's up to you, but I'd slot 3 Hami-Os (Dmg/Rng), 2 Acc IOs (note: I've never bothered to see if I could get similar levels of Accuracy from combining 2 IOs from the same set to get bonus slotted in there...if such a thing exists, that would be another alternative), 1 Proc from a Ranged Damage or Defense Debuff set.
Bright Nova Detonation / Scatter. These powers come for free but have a lot going against them. The new PvP rules have made the damage on these powers so miniscule that they almost aren't worth the endurance. You could use 5 slots on one of them if you wanted to slot a Purple set (like Ragnarok, I think) but that's the only way I think it would be worth using any slots on these. Even fully slotted these would only be semi-useful against an MM, but even then you're almost better of spamming the single-target blasts on the MM himself. I personally put a Damage IO in both of these and left it like that - no extra slots or enhancements. I have only ever used them if my recharge has been slowed to nothing and they are the only powers left available to me. Like I said, you could use one or both as set-bonus mules but I don't.
Some other thoughts on Bright Nova...it's great that you can't be mezzed out of it! One of my best escape tactics is just flying straight up with this. It also has an extra bit of flight reinforcement, so things like Impale and Air Superiority won't ground you while in this form. ***However*** most Villains these days are packing some sort of webnade-type of power and that will be your biggest obstacle using this form. If you get grounded, you lose your tactical edge, but you still have a pretty good amount of firepower, so I'd advise that you quickly assess the situation and decide if staying in Nova and fighting it out would be better than switching to the relative safety of Dwarf form. If you have more than one Villain on you, I'd recommend the switch to Dwarf while grounded. If it's one other enemy (and depending on the AT) I often continue the fire fight.
Tactics...Like I've mentioned before, the tactics while in Nova form are pretty straight forward. Hover, locate your target and start firing. I'll often hover quite a bit out of range, spot my target and go to where they are within my range but I'm still out of their range. This will afford me to get 2 or 3 hits in (at least) before any retaliation. I often will hover in Human form, hit Build Up, then shift and start firing. If you spot another aerial opponent, I'd try BU + IS (to ground them) then shift and fire away. It's a pretty good opener and will put them at a disadvantage.
***Human Form***
I'd concentrate my slotting in this way:
6 slots for Incandescent Strike. It's your biggest hitting power, does -fly and has a short stun component. I have a set of Hecatomb in it, but if you can't afford that, I'd recommend Crushing Impact or something like that.
5 or 6 in Gleaming Blast. It's good to have 2 or 3 attacks in Human form. Although I never fire off more than 2 at any time unless there is a good reason not to switch to Nova. Gleaming blast does -def and has decent damage. Choose from ranged damage sets (Purple if you have the money) or other decent sets...Thunderstrike for the +Accuracy things like that.
Essence Boost and Reform Essence...You can do either of the following:
5 slot each of these and Frankenslot them for max heal and max recharge. You save 1 slot on each power by doing this and still have around 95% heal 95% recharge. The downside is no set bonuses.
The other alternative is 6 slotting these to get the set bonuses (such as Dr. Wounds) and use the final slot to make up for recharge time or even put a +regen / +rec IO like Numina, Miracle or Regen Tissue. You'll want these two powers up as much as you can.
You'll want the following powers as well:
CJ, SJ, Hasten, SS
You come with Hover and Fly automatically but having the other travel powers is handy when you're trying to escape and/or chase someone down. CJ is a good place for an LoTG, and I'd recommend 3 recharges in Hasten and if you can spare it put and extra slot in SS and SJ to boost your speed. You could also throw in the Stealth IO in one of these powers or put it in Energy Flight (which you'll also want to 2 or 3 slot).
Get Quantum Flight as well...it's your Phase power - it's an end hog but you can offset that with Conserve Power or putting a couple of End Red enhancements in it.
I also chose Stealth to stack with the IO...it helps against some of the Villain ATs who don't have heightened perception. I actually 5-slotted stealth and got the bonuses from Red Fortune.
You may have noticed that I didn't get any of the Shields...I play my PB more as a Regen/Healer than anything else. If you can't survive using the 2 human form heals and the Dwarf Heal AND Phasing with Q Fly then you probably won't survive with the shields. Also, I spend so much time shifting in and out of Nova that having to retoggle 3 shields is cumbersome. So...I recommend ignoring them all together.
One thing you can do, however, if you choose to get and slot 3 quickly cycling human powers is to 2 - 3 slot Light Form, which will give you max resistance (in PvP about 40 - 45 %) and let you run around like you have shields on. That's one way to play both Human and Nova for some variety. Of course, you won't have access to Nova or Dwarf while you're in it and the crash is nasty and the recharge is long, but it is an option. You could also take and 3 6 slot Tough and get in the area of 27% resist to all with Tough and that AT inherent damage resistance.
Also, another power to look at is Photon Seekers. Long recharge and high end cost aside, if you're in melee with someone and this is at least 3-slotted for damage, it can do in the area of 400 - 500 points of damage. Together with IS this can be a pretty good opener. Of course, the seekers are still kind of messed up and don't always go after the target that you want them to go after.
*** Dwarf From***
I used to love Dwarf. It was so sturdy and had TP, which would let you survive a gank and escape without any issues. Since the changes to TP (suppression) and diminishing returns on resistance, Dwarf is pretty sturdy, but not as tough as it once was. It does give you a nice HP boost and will protect you in a pinch, but I mostly use it now for its heal.
I'd slot the form itself with 3 resistance IOs (or use 2 and 1 slot for -KB IO). This will give you in the area of 45% resistance to all but Psi. I use one of the attacks for another Purple set (Absolute Amazement in WD Strike). If you can't afford that, I might skip slotting that power at all. I also have a Purple set in the AoE (5 slots) but would probably skip that too if I couldn't afford the Purple set...or I'd switch it out for something else. I have 6 slots in the heal to max out the heal and recharge. Default slots in the rest of the power. Frankenslot the heal or use it for a set bonus.
1 last note...I have macros set up for each of the forms to drop me out of Nova or Dwarf into each of the various travel powers and Q fly. This way, if I get in big trouble in one of the forms I can drop out and phase with one click of a button. It's also handy to drop from Nova into fly if I'm high up. In fact, using these macros you can go to Dwarf, hit your heal and drop back to human and fly and use that heal in an aerial battle.
Anyway, I hope this is helpful. Just make sure you practice, find what works best for you and have fun. I love hover-blasting with my Nova so this is the style that I'm most comfortable with.