I've heard PG's are very tough to play in that mode unless you're cheesing it. I only played association mode for a bit before getting sucked in by My Player. I actually sold the game eventually due to the mode being incredibly buggy (after shelling out for Draft Combine) as I couldn't play for the Bulls no matter what I tried.
My bro-in-law gave me his copy a few months ago and I started over from Draft Combine as a 6'9" PF and averaged a double-double from pretty much the beginning. Got drafted rather high (R2:P6) by the Grizzlies, but didn't get an invite out of the summer league despite putting up good numbers. Ended up getting in with the Bulls instead (obv) and played well enough to get a chance in the NBA as Gibson's back up. Got my first start after 16 games, and eventually started getting so many minutes they traded Gibson away!
I finished the season just barely averaging a D-D and helped improve the team from playoff hopefuls to 3rd seed in the East (got ROTY as well). Got past the Wizards in the 1st round and swept the Heat in the 2nd, after which there was no way I wanted to give up, so I started cheesing it.
We faced up against the Cavs in the conference finals and took the series after a ridiculous 7 games! All the games we lost were by something like 20 pts but won all four games by a bucket or two each. Beat the Thunder (lol) in 5 games to win the championship, I got finals MVP.
Following that performance, apparently the Bulls didn't want to offer me a new contract (:laugh) and went with Ben Wallace instead. I was told to pick one of Hawks, Nuggets, Lakers, and Nets. Naturally I picked the most exciting team that I actually like, the Nuggets, and started the next season placed in the starting line-up ahead of K-Mart.
It turned out to be a great decision as I love playing in that team much more than with the Bulls. In Chicago, I often had to take over the scoring load whether I wanted to or not since Rose is a pass-first PG and didn't want to take shots no matter how many times I'd set him up perfectly. With the Nuggz, I play my role and let Melo and JR do their thing, as a result I've really improved my numbers in a massive way and we're the best team in the league right now (rated 97 at the moment, with a record of 30-4 so far).
What's really great is that I was the perfect guy for that team. I love scrapping for rebounds unlike the rest of the team, and actually like playing D, as a result of which I'm the NBA leader in points (we pretty much share them between myself, Melo and JR), rebounds and now even blocks, and have had two triple-doubles so far this season. The Bulls on the other hand are at the bottom of the power rankings...