youtube channel w&m levsha seems to show success cutting some metals with a cheap laser engraver by first oxidizing the surface black, then somehow lasering it off, and repeating the process a mind-boggling number of times to cut all the way through a thin sheet. is that a thing you have tried? what obstacles did you hit?
the advantage from my point of view is that you can cut the metal to an arbitrary shape, which no other tool can (though edm and ecm can, and in that video he mentions 'etching' as an alternative, by which i suppose he means photolithography). in this case he isn't really taking advantage of that power
Etching is remarkably precise and efficient, I've made 100's of small parts in one run, for very thin metal it would definitely be my process of choice.
for example in https://youtu.be/PAFBkgawH3w?t=2m10s he says he cut through a razor blade in 600 passes