I fly a Schweizer 300C from KBJC near Denver (fld elev. 5670). The 300C has a max cabin wt. of 600 pounds. I'm only 155#, but I often fly with an instructor who weighs in at 240. When the temps top 35C (9400+ Density Altitude) we have a pretty limited fuel load, but we can still fly!
I've actually never flown an R22 so can't speak about the type, but I've been very happy with the 300C.
Down near sea level the 300CBi would be another good choice with lower costs than the straight 300C. All depends on whether you can find a school you like within easy commuting distance- you'll want to fly at least 3 or 4 times a week (or more) to make best progress (least outlay $$$)!