I disagree with the premise that Ray's future determines the blow up probabilities.
C's are sliding downhill in talent due to the declining skills of KG, JO, Ray and PP. The team is out from under the contracts of all but PP next year.
They can stand pat for the year and let those contracts come off the books and try to get a good player through free agency->they're not getting Dwight and no one else that's a UFA is worth anywhere near the max. Still a good player may be a available--the question is, with a better FA class next year, do they bother getting a good player this year or go all out for 2 really good players the following year. I'd prefer the latter.
The other option is to move the vets for lesser-quality players that also expire and come with a draft pick OR move them for a equivalent player on a deal through next year with a 1st rounder (or more) to compensate for the extra cost. In short, build up as much draft picks and young players to be either quality players or quality trade assets for good players.
Bottom line, C's won't get far this year no matter what they do and they won't get far next year either because there's just not much out there that they could reasonably get that would turn this franchise around.
The following year, that's a different story. C's could have just Rondo and PP on significant contracts. Bass, Pietrus and Green as potential resignees. A couple of good draft picks from this coming draft. JJJ with hopefully a year of gametime under his belt. Bradley, Moore and Steimsma developed as either decent role players off the bench or off the roster in favor of better players. Add that in with plenty of cap space to go after 2 really good FA's that year, C's could be back in business in 2 years. Think Harden and Love/Griffin that year and the C's are looking pretty good.