Tommy was cool, but I also like CJ, because, like Tommy, he worked his way up from a petty thug to a considerably large influence in the criminal world. THink about it - he's Madd Dogg's manager, he gets money from all those businesses around San Andreas, and most of all, it's fun to watch how his skills improve. He starts out a petty gangbanger robbing fast food resturaunts, but at the end of the game, he's shooting down Air Force pilots with a stolen jet.
And besides, Tommy is pretty much alone. CJ has his brother and sister and a lot of cool friends, Zero, Woozie, Truth, Ken Rosenberg, and Kent Paul & Maccer.