I think you're onto an interesting experiment. I doubt that you'll beat the feel/use of the tools you named (at least not first go).
I've always admired people who can do things with metal (especially at home), I was never any good with the stuff even at school.
Just a thought, your variable angle tool, you'll probably need a second joint so that you can keep the cutting top in line with the tool shaft and centre-line for the larger off-set angles, or it will either roll in use or just plain rip itself out of your hand.