Actually, the system I am proposing would not be too different from what we have now, you got votes which are worth a certain quantity of vests depending on the vests and VP you got and the % you vote with.

The difference is that this vote will evolve around a fixed point (the value you set).
Meaning, if the value of the post is under the value you set, your vote will contribute to add more and if the value of the post is above, it will remove from it.