(Side editorial note:) Sorry I had to vote this down. It doesn't seem to have enough meat on it, imo, and what does AIUI mean? But even if it did we've discussed this lots of times already either directly, or in sub-discussions.
See here, here and here for starters.
With respect to your idea, I don't really agree. If I vote something to a section it means I'd prefer not to see it on the front page. Often this is because it's not an ultra-high standard.
If we don't have any really good stories for a while, what good will it be for the system to start issuing ultimatums about putting average stories on the front page? Change the voters' attitudes - not the way that their vote is interpreted based on a desired outcome. If it's desirable to have more front page votes, offer an incentive for people to vote front page.
The front page is just for marketing to people who haven't seen the site much before, and they're not likely to have seen the same story there for ages anyway.
jesterzog Fight the light