Agreed.
The 6cyl would be the go to mostly because difference in fuel mileage isnt much at all, transmission selection (the 5spd ax-15) is better, difference in input splines for transfercase is different 21 with 4cyl and 23 with 6cyl (makes swapping a dana 300 in the possible future a little easier), the great reputation of the 6cyl with how common they are and most of all you get that little bit more power.
I like YJ's simply because they are simple and can be bought fairly cheaper than the TJ. If your into the lift kit options theres alot to choose from and they seem reasonably priced. Theres really not alot to leaf springs and shocks. SOA or SUA to me mostly depends on the buyer and their preference. I like my SOA for the trail but for some reason SUA seems better suited for the more road friendly rigs that do see trail time of course but not the balls out hardcore stuff.
You already own a zook so ill go out on a limb here and say your "smart"
with your money and the biggest trap people, AT A TIME myself included, get into with these rigs is the aftermarket garbage that follows them. You can build a real trail and street worthy rig without all the unecessary junk, and it is JUNK, thats pushed towards jeep owners.
MOST OF ALL no matter the lift kit, tire size and all that other mumbo jumbo the biggest thing your gonna want to invest in with a YJ or TJ is a stronger rear axle (im biased towards the ford explorer 8.8) and a SYE (slip yoke eliminator).
My 2centz of course, to each his own. Long rant, but I hope this helps:beer: