As Mrs D said, look at the AP room discounts as gravy on the potato. If you make enough visits, it makes sense. There are several web sites out there that do a bit of a break over point analysis between getting regular tickets or APs and when it makes sense. Seems like somewhere around 8 days, the AP becomes the no-brainer. For us, it always makes sense. We're in Florida, and it's still a 6 hour drive, but we like to do one full blow-out week (Friday to following Sunday - 8 nights, 9 days) and then at least one -- but usually more -- weekend jaunts.
We're doing the Silver Pass this year, looking at the blockout dates, those are times we rarely ever go anyway.
As far as room discounts, mousesavers.com goes into quite a bit of detail about how they work and when they might hit. I just reserve the rooms I want at whatever rate they charge me, and check back with the CRO every few weeks to see if any discounts are available. I've not met a cast member unwilling to give us the better rate even for a room we've already booked.