I say if you want the draft to go faster, simply make it 2 rounds per day with half hour slots. I think people picking at their time slots is perfectly reasonable. A lot of folks don't "draft watch" regularly. I've had busy periods when I've only been able to check in at my known draft slots. If I know in advance when it's my turn to draft, I can check in some minutes early, read the board, do a little research, and make a pick.
I'd be fine with 2 rounds per day.