Im not sure about lifeless, well, my necromancers hut is technically lifeless i guess- but i do agree that there is a lot of oppurtunity around housing features that people are more than willing to sink time or money (hopefully its more achievement/reputation based) into potentially having for their homes. I wouldnt be lying if i said i wasnt one of them!
My one concern is around providing a unique or rare item/mats/benefit for higher level guilds. I have been around for this implementation in a few MMOS and it seems as soons as this concept gets to the point of benefiting someones raid numbers or pvp game, we run into the problem of mass-invite umbrella guilds based on "we got it all" and elititism that often renders rp guilds, new guilds, and otherwise those yet to max everything out as obsolete.
Now, being able to join and be part of multiple guilds itself might be the difference that lets zenimax get away with having the best of both worlds, so long as any benefits you might get from one guild do NOT stack. This brings up the question of why a player might then level up their other guild though.
Still. The idea of building upon and adding further depth to what we have could really breathe life into old systems.