We have points at the 4 WDW
DVC resorts, all of them bought directly from Disney, and we have two different use years. So far, I don't see a problem with managing them.
All but the BCV points have a December use year. We bought February BCV points because we would have those points available when the resort opened (we took DGDs in August, 2002) and if we had gotten December points we wouldn't have them until December, 2002. Not really all that big of a deal since everyone could start making reservations at the same time for the opening of BCV and we had other points we could use. I do think BCV February use year is a good fit because we are most likely to use the BCV points in the Spring or Summer.
Another very unlikely consideration was if for some reason there was some huge assessment (for instance YC, BC & BCVdecided to/needed to make some major changes to SAB) and we decided not to participate that it could affect our other points. Again, I think this is highly unlikely and truly I am not concerned, but it was a consideration. My DH wants to be certain that nothing I do will affect our OKW vacations. LOL. I am not aware of anything like that for SSR.
Now thanks to all the knowledgeabe DISers who generously share on the site, if we had it to do over again, we would probably buy all 150 point contracts. It may be easier long term to give/will/sell them, even if it takes a little more bookkeeping along the way.