How good are you? I'm very beginnerish. 70' is perfect for me to go wake to wake on the heel side, but a struggle on toe side (mostly cuz I suck). The more weight in front, the rampier the wake will get, the more weight in back the steeper. As a beginner, I like it rampy, so I'll fill the center tank and put a 400 in the bow. See my profile pic for an example.
Surf wake is pretty good... won't mistake it for an Enzo, but definitely surfable. For surfing you really need to weight the rear surfside locker, whether by pulling the hard tanks and replacing with fly high 750s, or by stuffing a sack in between the tank and the engine. Then a 400 on the seat and 300 in the bow and it's totally surfable. Decent surf wakes can be had with less weight, but that seems to be about as much as I can comfortably run. Oh and wedge down for sure. I find the wave really lacks push without the wedge, even if it looks OK.