While I think Richardson would be an ideal return for Ray, I think Barbosa is in the same category as Hinrich, Posey, and Nocioni. They are decent players, but make way too much money beyond this season for the C's to take them on as bench players.
If the C's can find a way to make a deal for Richardson, without having to take back Barbosa's salary, then it makes sense, but Barbosa makes this a non-starter I think.
I think we're going to have to take on somebody like that if we want to get an ideal return for Ray. If we can't do that, any trade is probably not even worth it.
The window is probably closed after this year anyway, so why worry about future salary implications, so long as it doesn't totally cripple the team? Even if KG / Pierce don't start to decline rapidly, at least one or two other teams in the league will probably get significantly better over the summer as we continue to move backwards. This year is our last chance - and it's a slim one even if we pull off a good trade.
Well, this isn't as much about "future salary implications" as it is about Wyc seeing exactly what you are seeing, and saying "heck no, I am not paying $90 million, plus luxury tax for a team that is not a contender." I personally believe that Wyc is not willing to continue to pay the luxury tax, if this team is not still a contender, and that Danny will not be allowed to take on bad salaries because of that.
Danny can look at this team, and see that if he simply stays where he is, and maybe picks up a veteran PG and/or wing defender off the buyout line, they have just as much of a chance to win a title this year, than if they trade Ray. And then he will have the money coming off the cap next year, and can explore sign and trades and MLE signings to help transition this team into the next decade. So it really only makes sense to trade Ray if they are able to actually improve the roster next season and beyond, without taking too much off the table this season, or improve the team this season, without hurting them in the future.
I guarantee you, you are not going to see Danny make a deal that raises the payroll next year and beyond, unless they are for very useful players on market-value contracts.