This is an interesting premise, but I'm not sure that the pool of potential grant recipients will be a very good one. The problem that I foresee is that people working on these sorts of projects seem to fall into two broad categories: -People who don't want to work for someone else, but lack vision and exist on social proof. These people will be attracted to the grant funding, but unable to use it to create something…
I 'run' my own micro arts fund providing support for people in MH communities that would like supplies or tools to help as part of their ongoing rehab or change of career as a way of getting back into a life that means something. The answer really is if you expect a measurable outcome from small-scale investing in people then don't do it, you're in the wrong space. If you view your investment as a path to the outcome…
If you approach it with the mindset of "let's free this person up for a while and see if this helps them do something cool" then you're more likely to be happy with the outcome.
This is not a job, after all, which would allow you to get a measurable or specific outcome - it's a grant!