Just my 2 cents, since I was exactly looking for something similar to kill again my social life again and go back playing an amazing mmorpg like the old good time of UO.
I browsed all games on mmorpg.com, I asked on differents forums, I tried different games (Rift was the most "similar", soon with housing and also a lot of crafting skills). But I can assure you - there is NO VALID alternatives at the moment! I mean, there are tons of mmorpg with amazing graphic and great story/gameplay, but if you are looking for the "social" part of UO, you will find it nowhere. No people spamming WTB xxx near Britain or Luna bank, just a cold, automated Auction House.
Especially, I used to be a rare collectors, or put together very rare armour pieces or artifacts. In any other game, there are of course "rare" items, but they are available to everyone. there is no UNIQUE or ultra rare items like in UO.
The only hope, for something new but same style, is archeage-online.com , coming out next year. So stay tuned. In the meantime, guess what? I bought a UO vet account (i repent so much i sold mine years a go) and started playing UO again. Just amazing! and so many new lands, skills, stuff. EA was surely not sleeping all those years. And they are now celebrating 15 Years of UO. If you miss UO, just stop looking elsewhere: come back to play it
