If our goal is actually to have good admins then we must be willing to remove the powers from people who misuse them. If we are already doing that, then we have no reason to worry about giving adminship to someone who will misuse it, since we could just reverse their actions and remove the adminship.
I agree, the main thing stopping relaxing adminship requirements is the lack of an easy way to desysop people when we make mistakes. However, even with an easy way to desysop, I don't think there would be net gain from relaxing requirements as much as you are suggesting. We could go with something inbetween. How about:
1) User requests adminship 2) Other users have a week to give reasons why they shouldn't be promoted, and respond to other people's reasons. No '''Support''' votes, support is the default. 3) After the week, a crat comes along, reads the reasons, and if, based on their personal judgement, there is not a good reason to withhold the mop, they promote the user.
The main thing is getting rid of support votes. You do away with them, and you remove any semblance of a vote. I've been trying to come up with a slightly stricter suggestion along these lines which involved coming to a consensus (or possibly just voting) on each reason not to promote, but I couldn't think of any way that would actually work. Just leaving it up to the crat makes it much easier (informal guidelines would probably arise naturally, and be ignored where appropriate). It requires trusting crats a little more than we do now, but I think RfB works reasonably well (and shouldn't change much, if at all), so that shouldn't be a problem.