No they don't. There are plenty of Japanese animated series that don't intentionally spoof any genre at all. Again, you can't make that kind of generalization unless you've seen every type of anime series there is, which clearly you haven't. Movie06, if you really must continually debate over these matters, it would help to actually have an a valid argument as opposed to just saying "anime is great" over and over again, because "anime > USAnimation" isn't a fact, that's just your opinion.
Yes it would, actually. Coop, Jamie, Kiva and Goat are all caricatures of American archetypes, not Japanese ones, so a anime take on those characters couldn't help but differ significantly from Cartoon Network's version. A better idea for a Japanese Megas XLR would be an anime that spoofed American sci-fi conventions, like HG Revolution suggested.