For manual guns, look for ones that has an air-bleeder valve. Its main purpose is for priming the gun waaaaay easier, especially for newbies. Don’t sleep on air-bleeder valve if you’re into manual guns.
I get your point, but for daily use? Plasma is just easier to use and more convenient. It has cleaner cuts and has no tanks. If you’re dealing with steel over 1/2 inch, sure, use oxy. But for ordinary job, I’ll go with plasma.
Yes it is possible, but it would take a lot of time and patience to do this. I DIYed a few canoe paddles and the whitewater paddle. It was tiring but I am so satisfied with it.