We already have two decent proposals, Avalanche and Storm.
But i had a thought, and its not that i necessarily think its a good idea, I'm just curious about if it would work.
What if there was a POS layer that pre-verified transactions before the miners got to them? Lets say, this is based off of the miners holdings, which they can optionally choose to stake at no cost, as its their computers that pre-verify them before the blocks are mined? I'm not suggesting any kind of an incentive to stake btw, I'm not sure if that would be needed if it was cost-free.
Would or could this work? Or what things might go wrong?