I know a lot of people tout UB as "too tough" or whatever - but I've been playing there ever since I started my foray into online poker, and quite honestly, I love it! I also think that in general, the quality of players *are* actually a bit better than some of the other sites out there, which means that you can play a much more "serious" game of poker at the lower limits. I'm not sure what your bankroll criteria are, but I'd actually recommend playing the 0.25/0.50 tables there - they are not quite as crap-shooty, but are still loose enough to be able to make money. If nothing else, I do think it will sharpen your game up for when you do move up in limits, because you can't always count on tables being so loose as to have 80% VP$IP.
I do definitely agree with briacheck - you've gotta log a couple thousand hands, at least, before your numbers (and particularly, your SD) start to stabilize somewhat. I'd say this starts to happen at anywhere from ~1.8k - 3.0k hands. At that point, you can really start to analyze your game, assuming your WR has remained positive...
BTW - I thought the same thing about Limit HE - and yes, it is a waiting game to a large extent. But I'd really urge you to start playing Limit, and grind through it for a while before you try and figure out NL.. The 'mistake' I made when I was starting out was *not* moving up limits too quickly, but rather, moving straight from Limit to NL, figiuring that "oh, well, it's easier, because I can simply defend my strong holdings that much better" - not realizing that figuring out the betting strategy to employ there is quite a bit more difficult than one might expect. I think you can only start to get an appreciation for how you should bet once you have some idea of how the betting limits in Limit HE actually "limit" your play. For me, this still something of a black science, and I don't play many NL games, since I still consider myself to be in the learning phase, after my 1+ year playing poker online. (To your credit, though, it seems as though you've really taken the time to learn how to play properly before making your first deposit; I don't think I was as conscientous about this as you appear to have been.) The one last thing I'll say about Limit vs. NL is that this betting strategy I refer to is not well-prescribed in books. Correct me if I'm wrong, guys - but it seems to me that determine how large (or small) to make your bets in NL is almost as much of an art as it is a science. This means that it will cost you a lot more in 'educational investment' than Limit will, initially - or at least, that's my sense.
Well, whatever it is you decide to do, definitely be sure to post your hands here. I've learned a lot from these guys, and I've been grinding it out at the 1/2 level for the past couple of months - it's boring and frustrating at times, and the urge to move up and/or find a different game is certainly tempting every now and again. But I'm showing a steady net-positive WR, and am doing pretty well, so I can't complain.
OK, sorry for the long post (unfortunately I tend to be verbose

)... hope there's some useful advice in there.
Good luck at the tables! (luck? I thought it was all about skill?

)