Boris Diaw is similar to JJ in a lot of ways but we're comparing his strengths to JJ not his overall game - nobody that averages less than 5 PTS in 18 minutes isn't a JJ clone... BUT
Diaw has similar ball handling, rebounding, passing ability, steals/blocks, height (6'8), and athleticism in limited minutes... if he averaged 40 minutes a game like JJ does - all these areas might even be better but doubtful he gets 40 minutes as a back-up PG
I've recently watched both of last years games and most of his minutes are at PG and he looked more of a playmaker than JJ but he just isn't the scorer... that might not mean much, JJ wasn't ever a great PG but Diaw and Barbosa at PG isn't much of a drop off.
The team will struggle at starting SG though but JJack has a game similar and IMO should be the starting SG, JJack averaged 1.7 3PTer made at 46% clip... both similar to JJ while on the Suns this year (not sure of overall #'s for Rockets and Suns together)... he's just not as good as JJ but I feel more comfortable with JJack than Bell starting...
Bell was a back-up on a horrible team and played nearly the same minutes but has been in the League much longer than Diaw (5-6 years older) - Diaw is labeled a unwilling scorer but his other numbers aren't bad. Passing, rebounding, Steals, blocks, with more height and better athleticism than Bell - right now and most people think the team is still strong without JJ but with Bell. Bell replaces JJ at SG and Diaw replaces JJ at PG... outside of scoring and shooting - Bell and Diaw are almost duplicates statwise. Diaw is a decent defender, but obviously doesn't have reputation as Bell...
I'm not sure why everybody is soooo down on Diaw (he is a pass first Point currently) and thinks Bell will actually give no drop off from JJ - compare Bell's and Diaw's numbers - the only area he's better in is scoring area's and scoring isn't all there is too game. If Diaw learns to shoot in 2-3 years, IMO he's going to be as good fit as Bell, although Diaw might not have as much toughness as Bell to become the defender but Diaw is a good defender himself.
I have almost 99.5% of every Suns game for 9 years and yes, I have no life and watch as many games as I can of the offseason moves... once the Trade is official I plan on watching Diaw's Rookie year and that same year of Bell's games. Then possibly this year's of Padgett's and if I have-to Pat Burke's Rookie year with Magic... when they sign. KT I am kind of more familiar with.