I had some great adventures in my '85 with it's SA and 22R.
The first thing I did was swap in a set of leather buck seats from a newer 4Runner. That upped the comfort level quite a bit. It was never a powerhouse but it was steady and reliable and took me to some fun spots around Wyoming.
My needs eventually changed slightly, but with a small suspension lift and some decent tires, it is a smart platform. I had envisioned doing a sub-$5K build up with it. Spare fuel, water and a sleeping platform would allow for going anywhere. It's lack of horsepower also had me looking at a winch, just in case.
A simple and reliable powertrain with good aftermarket support should make for an "easy & economical" build. I would start learning as much now as possible about tweaking carburetors if you plan on travelling to areas with varied elevations.