I'm definitely going to agree with BeeJay to a point... Logic's drums are not stellar (they're okay, but that's as far as I go), and forget Ultrabeat if you want a little bit a "realism". However, if all you have to work with right now are Logic's kits (and perhaps the Rhythm Section JamPack), go into the EXS and separate the important groups (kick, snare, toms and hi-hats) into their own aux channels and save the the instrument as a multichannel instrument. Work with the separate aux channels by adding in a bit of EQ and/or compression (or do the New York style mix). As well, send the unprocessed signals to a bus containing a drum room reverb and mix them together.
Another thing you may want to consider is the fact in order to sound like a human, don't play it like a robot. Quantize certain parts, but not every part (and it doesn't have to be at 100% - use lower strengths to bring out a bit of humanness). If you don't have one, get a pad input, such as M-Audio's Trigger Finger. Note the a lot of the kits in the EXS and JamPacks have a few articulations for drums that you need to make use of, such as flams, drags and rimshots to do various beats. Listen to various rhythms and fills and watch how drummers do it (plenty of videos on
http://www.drummerworld.com). And, when you make a beat, play the beat.
Back to samples: if you find that Logic's kits still aren't cutting it for you, definitely go for something like BFD, DKFH or whatever. I fell in love with BFD and highly recommend it. As to whether it sounds like a drummer for you will depend on how you play it. For me, it definitely sounds like a drummer. :-D
jord