Low RPM is pulling (pushing) power at slow speed. A SUV that is used for 4x4 applications needs a bit of that really like a tug boat. Neither of these engines is bad for doing over 160kmph on motorways, but some engines will suit you better for taking 9 people and stuff up Babusar Pass.
1hd-t
1hz
These both are diesel engines and your vehicle might have one of the two. Perhaps even a 1hd-ft that was even a bit more powerful.
If its in overhaulable shape - By all means overhaul it.
If you want petrol for some particular reason the 1fz is better than the 1uz. Its an expensive swap that with all possible costs could go upto 600,000/-
Id suggest a 1hd-t rebuild. Or sell your diesel engine and trade in for one thats a little better.
Engines to stay away from but will be recommended by mechanics:
3L or 5L
1kz
5vz-fe
1uz Fe
All of the above lack the power and/or have severe issues that need to be countered during the swap. 9/10 times you will end up with a engine prone to overheat situation.