Just wanted to say, that there is really no difference in level of service when buying resale vs. Disney. BCV's does not offer any additional benefits per se. You do get the use of the BCV's pool, which is very popular, and you are also just 5 minutes from the EPCOT gate, so those are the two benefits that are intrinsic to the BCV's.
If you can never book between 8 & 11 months in advance, it really doesn't matter where you own, because at 7 months you can book at any of the DVC resorts. I would certainly buy at an on-site resort though.
With a 750 point contract I think I would have offered even a bit less, 57 or 58 per point. Disney may buy it back at that point, but it's worth a shot. It would probably be good to buy a couple of contracts to add up to the 750 points if you are worried about resale value.. smaller contracts (250 or less) seem to sell much more quickly (within days), but you'll pay a lot more for them if you're looking at WLV or BWV's, you can still get a 250 point contract at OKW for low 60's it seems....
Do email Shontel at the email address above, she's very experienced with DVC resales, she worked at the Timeshare Store for years. Good luck, it sounds like you're doing your homework!