Well, the first thing that goes through my mind is if you think you're having little problems now, trading it in on a Ford is going to be the nightmare from hell, IMO. That is unless you're going to buy a brand new one. Then you might get a good year or two out of it.
I know I'm bias, but seriously, I've driven dozens of domestic vehicles, including Fords and they just have one problem after another. Especially electrical problems.
As for your issues. If you don't hear any noises, your chain is probably fine. Don't worry about it right now. Worst case scenario, 22RE engines are dirt cheap comparitively, since they are so plentiful. If you just purchased the truck, it might have already been replaced. If you really worried about it, then just replace the chain. Parts are cheap if you get them from EB. It might take you a day to do the job, but it will help you learn about the truck also.
The wiring hanging down should be super easy to figure. Give us some more details.
The most common oil leaks on the 22RE are valve cover gaskets or gromlets or half moons which are super easy to fix. The other likely cause is the front oil seal, which is also not that difficult.
Not sure about the bucking. The tires leaning might have to do with the torsion bars being cranked up. Just get an alignment and have them reset the bars to the stock location. You might possibly need a new steering idler arm or rebuilt it.
The thing is, even if you had to replace all of the above items, including the timing chain, that's remarkably simple stuff for a truck with 165K miles on it and you'll probably get another 100K out of it, relatively trouble free.
The primary reasons for keeping a Toyota is they are extremely reliably, durable and very cost effective. They're cheap to work on and parts are cheap and plentiful.
Show me a similiar type Ford mini-truck that has similiar mileage and I'll show you a truck on its last leg. Many of us are running Toyotas with 200 or 300K miles on our original motors, trannys, etc and we're beating the snot out of them on the trail, not babying them on the highway.
That speaks volumes.
Just my opinion. Good luck.
