Joe Johnson is still good as long as you don't expect great defense from him. He can still score 1 on 1 against many sfs in the league. Those floaters are annoyingly accurate
Don't forget about his post game and midrange, either, but even more than his scoring, his passing coupled with his intelligence and ability to draw double teams would be a great fit here, and he'd certainly be the best passer on the team since Rondo was traded

. I also don't think that it's a coincidence that Joe's had 4 out of 5 excellent games since Jarrett Jack went down. I watched a few Nets games and that guy sucks. I don't care how many assists he'd end up with, the dude is a ball hog who would go entire halves without getting Joe more than 4/5 shots. In one contest, Joe played around 10 minutes in the first quarter and didn't get one shot, only to get 2 in the second quarter

. How are you supposed to be able to establish any kind of a rhythm under such circumstances? Ugh.
Admittedly, I do think that he should lose 15 lbs to get down to 225, because he's just carrying too much weight at this point in his career, even though I realize that he's always been that size. Lebron lost 10 lbs., didn't he? I just think that it would really help Joe's quickness and give him his legs back. Hollins, who is an atrocious coach (if you don't believe me, take a minute to visit netsdaily. The guy is horrible.), had him playing way too many minutes. Cut his time down from 35 to 28-30 and he'll be fine. Let him identify and exploit mismatches (what a concept! (sarcasm)), play intelligent basketball (again, what a concept! (sarcasm)), and set people up for most of the game and then have him take over down the stretch. I'd also be interested to see if he could help a guy like James Young in his development.
Obviously, if all of that worked out, I'd love to see Joe finish his career here, but I seriously doubt that he'd be up for that as opposed to joining a contender at this stage of his career. I still think he's a starter for right now, but those minutes would have to be cut. After all, we're talking about a guy who has played more minutes over the past decade than anyone in the league not named Lebron James.