I'm thinking of getting smaller fins...mainly to help with riding blind. I just wondered if smaller fins would also increase the pop of a board?

The only thing outside of technique that effects pop is your board. The stiffer the better. The more a board flexes the more energy you lose as you load. You don't even need fins to ride and throw tricks. I personally ride with wake fins or no fins at all. 2" fins just are not needed.

what thejoe said but if youre riding in chop bigger fins can be better so you can actually hold an edge to load against, i ride 1.5" with straps and boots just so I'm not constantly skipping around :/