Just thought I'd chime in and say I think it's really odd that people are talking about Powerplay in Open potentially having extra rewards to 'make up for the extra risk'.
I agree with the extra rewards, but I think it's the wrong way to look at it. It should have extra rewards to entice people into open, to promote it and to give players a legitimate reason to do things in open. Player interaction can be pretty fun. If you don't like being blown up because it hurts your feelings, then you can always do it in Solo and your contributions will still count.
Only really saying this because I do think Open Only PP would be nice but FDev doesn't have it in them to implement that into the game