Why? We already have Jeff Green (assuming we re-sign him, and we should). Rashard fills almost precisely the same role as Green, without any of the upside.
Of any of the higher profile potential amnesty guys, Baron Davis and Brandon Roy make the most sense, though I think I'd rather re-sign Delonte West. Mehmet Okur could be the best option, though I'm not sure how much game he has left.
Rashard is a much better defender at the 4 position, he's more comfortable with it. We can let Green be a full-time SF with Rashard here.
I think Rashard Lewis would work well with KG.
With Paul Pierce starting, using Green as only a "full-time SF" means at most 20 minutes a game. Doesn't seem worth the money we'd be paying Green; it also wouldn't help him develop much into the future starting role we seem to hope he can grow into.
I would see Lewis as a full time power forward with Boston. Jeff Green needs to play more minutes at the SF spot. I don't look at them as the same player.
Perhaps not, but my point is that Jeff Green needs to play more than 15-20 minutes a night and he's not going to unless he gets some time at power forward (he's not gonna play SG or C). If we have both Rashard and Green on the roster, even if we view them as substantially different players with different roles, the problem remains that one of them will have his potential playing time significantly reduced in favor of the other.
In other words, combined the two would only play 35 minutes or so. That doesn't leave a lot of room for both to have a role commensurate with their cost (or interest in playing here).
Unless you move Kevin Garnett to the center position and start Rashard Lewis at PF.
Play a one in four out offense with Rajon Rondo running the show surrounded by the best collection of shooters (Ray, Pierce, Rashard and Garnett) in the league.
Use Jeff Green as a combo forward sixth man, similar to Thaddeus Young in Philadelphia, to get him somewhere around 30 minutes a night too.
Play Jermaine O'Neal as your backup center and keep one of Garnett/Jermaine on the floor at all times to provide interior defense.
That team would struggle some on the boards but it'd be the best offensive team in the league + a well above average defensive squad.