Any argument involving the quality of the names being freed is silly, in all honesty. One man's quality is another man's trash. If your definition of "quality" is merely only the names that you, in particular, want, and can't have at the moment, then the name-purge process would most likely disappoint you, no matter what level the cut off is, or how long the grace period is, or whatever other stipulation they might decide to place on it. Stop bringing in subjectivity into this. The only logical way to do this is exactly the way the dev's plan on doing it...setting a reasonable level cap and grace period, based on datamining and internal testing , and seeing what comes out the other end.
And honestly...for every lvl 50 that is mothballed, there are probably 10 or 20 times that many lowbies not being used either. Simple math says, go with the strategy that yields the biggest number. Again, the devs have found a solution that fits.
A question to the devs: Is there going to be an email notification sent out to all accounts, both active and inactive, about this? If there are people overseas or otherwise unable to play the game, but still have access to email, they would be able to contact you and request some kind of extension, or personally verify that they would like to release their names to the current customers. I'm not sure how easy it would be to verify whether Joe Blow is really in Afghanistan or not, but it would seem like the proper thing to do to at least offer the chance for them to make that decision, since most of them got shipped out with little notice, and are most likely coming back sometime soon, and would like to resume their game.