Good point. My main concern Is that the one with 4 doors I like are pretty damn long. Are they still gonna do fine going over sharp hills or valleys without dragging the rear end or high topping ? I know even my friends Cherokee drags its trailer hitch ball on some of the sharp valleys (I'm not sure if that's actually the right terminology for the terrain)
What you're talking about is quantified in the off-roading community in angles. Most commonly compared and published are approach, departure, and breakover.
Basically approach is the angle you can drive into without scraping, departure is the angle you can drive off of without scraping, and breakover is the angle before scraping in between the front and rear axles.
For used model trucks that you might be considering the angles are:
F150 - Approach 26 Departure 24 Breakover 16
4Runner - Approach 30 Departure 26 Breakover 22
Grand Cherokee - Approach 34 Departure 27 Breakover 20
Keep in mind these are measurements with stock wheels/tires/suspensions/bumpers. You can increase these numbers vastly with a few aftermarket purchases.
Also remember that pickup trucks vary in length quite a bit, while SUVs do not. Very few SUVs have different length variations, and theyre mostly the large ones. (Escalade vs Escalade EST and Expedition vs Expedition EL) Pickup trucks usually offer quite a few cab/bed length combos. For example, you mentioned the 4 door F150s seemed long to you. You can get a 4 door F150 SuperCrew (full doors) with beds from 5"-8", and that 3 feet can make a big difference.
As for if they would do fine, I go offroading a bit in the Phoenix area to get to shooting spots or hiking trailheads(I live in Mesa). Nothing serious, and I only drive an Explorer with minor modifications (not the new crossover model/the previous generation with the truck frame). If you're towards the shooting spots that I'm thinking off like the washes towards Tonto/Beeline or south outside QC then you'll be fine with minor tweaks to any major manufacturer truck.
Part of offroading in the desert is learning to drive up and assess the terrain and pick out routes. Out here it's great since we don't have to follow an exact trail rutted out for us where there isn't even 2 feet on working room on either side of the truck. You can back up and approach another slope, and learning how to do that and what angles to take will allow you to reach the far majority of places without needing a very specialized 4x4.
Next time your buddy takes you out to the spot, stop and take a measurement of what you think the steep angles are, you'll probably be surprised. A lot of internet ninjas will say they go up 40+ degree slopes all the time, but people I've gone out have balked and stopped the truck thinking they get drove up to a solid vertical wall when it's not even 10-15.
