Quick question. Why?
There are many factors that can make this sort of map an unfair game.
For example: What if a team is stacked? The other team wouldn't stand a chance, for there only needs to be 3 points capped. Whereas on regular CP maps, 5 points gives them a chance, let alone both teams if one isn't power stacked.
I mean, it's a nice concept, but there are things you'll have to do to even things out for both teams.