the housing situation, and the abandoned cities etc, is an ongoing problem, there have been many solutions put forward, the one that appeals to me most however is the house packup to datapads, as nobody loses anything, except of course those with houses for char's that no longer exist - an exploit btw, that people abused imo, in order to gain more storage etc.
The main downside from SOE's standpoint is that it would be an admission of failure, with so many cities disappearing from so many planets, on each server, though tbh, a cleanup is long past due, it would also make it harder for new cities to come into being, even in the past, cities relied on the 'inactives' to maintain city sizes, its unlikely that any new ones would be able to progress beyond village size. this imo would also be because there is little reason for people to actually create a city any more.
the problem isnt that the galaxy is too full, but instead, that its too empty, what i would like to see is house automatic pack up, when the maintenance of a house reaches 0, this would only work though, if the only person who could put maintenance in a house, is the owner of the house, and not just anybody on the housing administrator list. which really, has become an exploit so that people can have more housing than they otherwise could.