'86's do have the aluminum control arms, but you can change just the ball joints, it takes a bit of work though. A friend has a much modified '89 and driven back to back against my old '86, there's not much difference, except in the power department. His brakes may be a bit better, but not noticeably.
Mine was still fast, but his is/was since it doesn't run right now, ballistic fast. Viper fast, Ferrari fast, as in stretch your eyeballs fast. Then it blows up.
As stated above, if you plan to do a LX swap, you definitely want to start with the turbo. Otherwise you're going to be sourcing all the turbo specific parts separately as you will need them.
Now, as to the question do you want it, of course you do. Everyone needs one. Do you want to endure the heartache that comes with it...hum...that depends.
I bought a similarly priced 951, and promptly spent 3 times that number getting back into reliable condition. That wasn't fun mods, that was just getting all the maintenance back up to date and replacing the timing belt that broke the week after I bought it. It only had like 29+k on the timing belt, so let that be a warning. Then there was the turbo itself, and the oil cooler that let go going up a hill. (that's the fun part where you oil down your back tires in rush hour traffic) Of course you can through in a power steering pump, oil pan gasket, valve cover gasket, rear main seal, clutch, and on and on.
Once it was done, it was a blast to drive and fairly reliable. Then an under aged kid lost control of the family van he had snuck out and shoved it through my building at work. It actually ended up in my office a few feet from my desk, but that's another story.