Well considering inflation has hit big-time since you left, I'd say at least activate your thief so you have access to all your gear and TH2. As far as coming back as a newb, wouldn't that mean you came back exactly as you left? :)
Yeah, and they're having that deal about the old adventurers coming back or something...? I dunno. I registered and tried it, but it didn't work, and I had to pay.