wow.. not sure I'm the best person to answer those, but I'll try. I bought OKW in 1995, sold it, and then bought in again at HH in part because it was the best deal at the time (around $70/point with banked points). I've never stayed at HH and I don't need points during the holidays and I don't need to stay at the high traffic resorts like BCV or AKV to enjoy my time there. So for me, it was about getting the most amount of points for the least $. Part of the annual dues (property taxes) are tax deductable, but some are not - maintenance fees for instance. DVC can give you a breakdown of the dues for your taxes. If you're financing the purchase you should check with an accountant on what might be deductable. If you have a mortgage now and can take advantage of current rates, it may make more sense to refinance and take out equity for an outright purchase.. depends on your cicrumstances, but I'd check with an expert on how best to do that.
I bought both sight unseen. It's prepaid vacation. I've stayed at BWV, OKW, and SSR. I've also used points to stay in NYC on the Concierge Collection. Never had a problem using my points 7 months out versus 11 at home resort. If it's important to you to stay at a certain resort during certain times of the year and have larger unit sizes, you should target those resales for your purchase. Being able to book 11 months out versus 7 can make a huge difference if you're less flexible in when and where you want to stay.

hope this helps.