Have you considered a lower pitch prop? That would probably get you out of the hole faster but like almost everything else, you will loose top end speed. Maybe a 4 blade prop instead of 3?

In a past life, I had a friend that had a prop that changed pitch as it ran. I recall that it was about a 16 until it hit 3 or 4 thousand RPM and then it switched to about a 23 for top end. It worked really well for the summer he ran it. He sold it the next winter but I can't recall why.