I daily drive my truck with 5.29's and 35's and get 18-20 mpg and 16-17 mpg towing a 900 pound utility trailer.
im currently running 5.29's with 33's and its annoyingly low geared i dont like running it faster than 50mph due to high rpm's and thats in 5th gear a 4speed would really suck but its great on the trail and i plan on 35's in the neer future and i think 35's and 5.29's will be great. my 
dude, i dont know what you call high RPM's but i run my truck between 1000 rpm and 5000 rpm and have for the past 15 years (ok its not the same engine but THIS engine has been in there 6 years) my original 20R was driven the same way and it lasted till 297,000 miles.
I almost never shift before hitting 3800. and according to old literature provided in the 80's from Toyota the 22R was designed to shift at 3600.
I regularly run down the interstate at 4000 rpm in 4th gear for the simple reason that requires about 1/3 less throttle than it requires in 5th to maintain the same speed.
