spent the weekend on a 2010 North Race LTD and a custom race board. Great fun. North board was WAY easier to ride than the custom beast and that was my first time on the North and my third on the custom. Great workout for my legs as it's all new muscles. My ankles did get a tad sore and knees felt mostly fine.
With my personal issues, I'd be nervous with a big wide board in chop since my front leg needs to be so straight. Straight is bad when you have loose kneecaps. Otherwise, racing is a sweet new challenge and I need to find the right board.
You can do a lot by just having a few different fin sets. The fins really make the boards very different.
I know North board and Amundson boards I have tried has smaller fins. It does make it easier to ride (somewhat), but you'll lose a lot of low end and upwind angle / drive.
I like the naish venturi board a lot. I think the thruster set feels a little smoother..that said, between rumors on the beach and protos laying around every now and then it seems next season will have a ton of new stuff. It is so much fun to ride around on. Especially when you have a whole bay to yourself, and everyone else is just sitting on the beach