Interesting, that's close to what I run but more balanced. Here's my setup;
Port tank - full
KGB - 3/4 full to full
Starboard tank - empty
Port locker - 1100 sack
Port storage under glove box - 750 sack
That gives me a decent wave for free surfing with just my wife driving. It gets better with more people, of course.
I'm going to try with the starboard tank full too next season. Can't hurt and will balance out the boat some. It's got a pretty good list with my setup. Oh yeah, speed, same as you, around 12 mph.
BTW, you are a big reason why we have a 40th. Last year about this time we were looking for a new boat. I showed my wife some pictures of yours. After that, every other boat she saw, she didn't like.
2008 40th Xstar
2006 ProStar 197 - sold
1992 Ski Nautique