FAA user fees

My AOPA renewal notice included another one of those blurbs about user fees.
Increased fuel tax, flight fees for turbines, etc. I wanted to throw out a
couple of questions....

What if ATC fees were limited to revenue flights, regardless of engine type?
Would dual instruction flights be included?

What if fees were proportional to the number of souls on board, or to the
aircraft's (net or gross) takeoff weight?

Also...is it true that airlines don't pay tax on jet fuel? If so, why has
nobody nominated changing that as a way of funding ATC? After all, it's the
airlines that reap the greatest benefit from ATC, not GA.

I know, the answer is always "the airline lobby." My idealism wants my
cynicism to be wrong this time.

-Scott