@Gringo, congrats on your acquisition. Your list...even your last post, provides you with a tremendous amount of necessary research here on the site. And this site is where to find folks who know the hard facts or can direct you to them if you can't find them in the searches or the FSM. You will stumble onto things that you had no idea was an issue because some kind, experienced soul here spoke up. For instance, you mentioned 31 or 33 tires. Tire size is closely interrelated to gear ratio. You will find a chart that shows where the heart of the size envelope is for given gear ratios. I certainly never knew until someone here mentioned it.
I think
@60Works' advice to take it slow is excellent advice. It will give you time to research various paths and creating a goal that results in synergy, as he describes. Also as he describes, a lot of people jump on this or that thing. Being the original owner of our '90 FJ62, I can tell you that some things have actually improved and may not need drastic changing. A lot of folks jump on the LED headlight and/or headlight harness upgrade. I thought I was headed that way because my headlights seemed dim as I began restoration last year. Turns out the old sealed beams were...old, and the light "capsule" in the steering wheel switch assembly was beginning to fail, degrading the load to the headlights. With the switch issue solved, the Sylvania replacements with their new filaments and a redesigned lens are superbly bright and full spectrum accurate color. Saved a bunch there.
Another thing to consider on our older vehicles is that the engine responds to every pound we add to it whether its larger tires, different bumpers, extra humans, dogs, gear, etc.. You will find that a drive on a nearby mountainous highway will tell you a lot about your vehicle. Do it by yourself, then take another human, some groceries, and the 80 pound dog. You might be surprised at the difference. You might consider only the front ARB bumper just to save the load on the engine if it seems to not want any more weight (or similar compromises). Also take a point and shoot digital thermometer and check the temp of the tranny pan on both driver and passenger side a few times along the way. That will likely be a real eye-opener. All these things "educate" you on the real-world condition and potential of your vehicle.
You might consider shopping around the forum looking at builds/restorations that had goals and aesthetics similar to yours.
And yes...it will be expensive, but this way you can program the investment out, even if you are not doing all the wrenching.
Good luck.