I also have a 2004 SSV and have gone through many configurations before getting it dialed in. I have found that the Gravity Games sacs offer the best configuration for having the ability to adjust from a beiginner wake to a pro wake, all with the push of a button. However, at $800 for the set of three sacs it can be pretty expensive. I had some custom sacs made a couple of years ago that pretty much copy the dimensions of the GG sacs. They cost me around $290 for the set of 3, but I don't think they are making them anymore?
My rear sacs are the same dimensions as the GG sacs, 19x19x42. They hold between 550 lbs to 650 lbs each. My center sac isn't as long as the GG center sac, but it fills up the entire basement of my play pen locker. It is around 850 lbs. I also have 200 lbs of iron weight lifting plates under the bow seats as well.
To make a long story short, I have approx 1200 lbs in the rear and 1050 lbs in the front. Here's a pic of the wake with ballast full, 3 people in the boat, and the wake plate all the way down...