I wrote this a couple of weeks ago on another thread and got yelled at,but if I ran the resorts, I'd close the parks to non-resort guests Tues-Thursday for all but the peak times. There'd still be plenty of people (since there are 90,000 in the resorts at any given time. If you trust TEA, then the MK averaged 52,000 people a day last year (and if you don't trust TEA and want to say that Disney doesn't release attendance numbers, then I don't know what to say to you). Of that 52,000, roughly 34,000 are resort guests. The average daily attendance in 2002 (just about the time FP- debuted) was 38,000, so everyone missing the old days would have a shot at them by staying on site. Then staying on site would be an appreciable benefit and Disney could charge more for their rooms. I don't think you need to tier the levels by resort category -- just scan their bands when they come, and if they're a resort guest, they get in. if not, they don't. I've run out the math -- Disney could charge $50/room on average and that would cover the cost of the 18,000 admissions they'd be missing out on for those days.
You'd still have the off-site guests and locals able to attend Friday-Monday, during the peak the times (June-July-August, late December, Presidents week, Spring Break and Easter). Lots of people would be pissed because it was elitist and unfair, but I think it's the best way to both enhance the experience for the guests who have given them the most loyalty (by staying on site). Because so many guests are from the resorts, Disney really can't offer them more fast passes or FotL, because logistically it wouldn't work -- if 2/3s of your guests have Front access, those lines on the headliners would be longer than the other standby.
The problems with everything at Disney is crowds. The only thing that improves the experience at Disney is by reducing crowds.