Two quick ideas for two zones I love:
Faultline: its highly enhabited by villains, why don't you have some rope bridges at some points where you could pass through on the eastern vahz side, some thinner metal construct bridges on the western side for the clockworks, and down at the pits put some CoT portals in. They'd portal you to some point close to the entrance of the zone. I had teleport and teleport friend so I would always go there. It was great.
Boomtown: This is an amazing zone. I will always go there at 10 or 11 and start inviting people who are LFT in Hallows to my group. Generally I'll lose people who have never been there or don't want to make the trip, but I can get a group and its just awesome until level 14 or 15. Its hard around 15 because there seems to be a jump from 13-14 mobs to 16-17 mobs. Honestly the WORST part about the zone is its SO dangerous to get to. You don't have travel powers until 14 and therefore you 10-13 wading through 15 council and outcasts. The best solution? Allow the yellow line to go to the green line in steel canyon and vise versa.
