I have an essex valor 24 with a 496 - whipple supercharger. Currently running a 29 pitch bravo 1 prop. I can hit the rev limiter pretty easy with this prop but it slips when I am just crusing slow. If I try to cruise just past where I plane off (25mph), the prop seems to randomly slip unless I have it trimmed all the way down. However, When I hammer it and build some speed, I can trim it up and hit 81 mph at the rev limiter.

Any suggestions on a prop? I think I need a 30 pitch to bring the RPMS down but don't think I want to go with a bravo 1 due to the slip issue. Just looking for advice.

Look at the propeller casting and see if it is made from a 30 or a 28 pitch casting.
If it is made from a 30, we should be able to use your propeller and alleviate the slipping and get you off the limiter.

Brett