Any 1HDx platform that is tuned and modified correctly will give you excellent power.
28psi, 250rwhp (irrelevant with a full time 4wd) and 600ftlbs is no problem. Some even run 32+psi.
I am not sure why you are comparing the 1HDx to the 1FZx. They are so completely different in nearly every way including how they drive on and off-road.
The concerns of parts, some random mechanic know what to do and so forth are valid. Most diesel Cruiser owners in the USA either work on their own truck or have “their guy” who they have and do work with at least some what regularly. They truly are not hard to work on with a half dozen metric wrenchs and an FSM. They need far less maintenance or repairs than the gas engines. All a diesel needs to run is air, fuel and compression. I have seen 1HZs running on 100psi in a cylinder for an engine that should have 500psi.