Ok this is just an all around good idea. Very elegant growth hack. Time sliced boosting at the whole org level provides convenient investment vehicle for booster, and sounds like implementation costs are reasonably low.
A minor note regarding terminology: inviting “sponsors” may attract a more palatable crowd than marketing to “investors”. That said, boosting entitles you to future grain distributions which stand to grow proportionally to orgs success. Unless I’m missing something (wouldn’t be first time ;), that sounds like an appreciating investment to me.