Hey Will, we had a 21V before acquiring the 23V in '03. I don't believe that any Tige comes equipped with a center ballast option and most that I know of don't have any built in ballast, period.
The turn into the wake, on my Tige's, actually lowered the height of the wake and created a bit longer pocket, while at the same time mellowing the transition more than I cared for. 11.5 is probably a bit fast, but realistically if folks are surfing it without issue the actual speed setting "number" is probably meaningless. We typically surf at 10.5, bumping up or slowing down when we are practicing for a specific contest and want to match that speed.
I also leave Taps set at 4 and then adjust it as we burn gas through the session - winding up no more than about 6.
In my experience, the weight in the bow tended to just crap the wake out. Didn't make it longer and reduced the height, also didn't improve the transition.
I purchased a few custom sac's that fit into the rectangular rear compartments...basically just filling that up with ballast. The other sac I had made fit into the entire length under the bench seat on the port side. That substantially helped the wake shape and size.
I got tired of all that messing around with sac's and finally had the folks from Fly High make me a custom sac, similar to their Enzo Sac that basically just combines those two individual sac, so now we have every square inch on the port side under the seats and in the rear compartment filled with ballast. I think I calculated it once as having a theoretical capacity of 1,300 pounds - it might be more than that though.
On the Starboard side, I use the old rectangular sac and a fat buddy that I jam up in the small space from the rear storage locker up to where the cooler stops. The starboard side is the weaker of the two.
This is what we end up with, that is with just 2 people in the boat totalling 300 pounds and with the custom sac filled.
Our 21 V had the same basic shape and size.