I don't believe, up to 5.5 levels, that you need to disquise your toss for top, kick, slice, or flat serves.
First of all, your tendencies will be known by your third service game. Second, the opposition knows the chances of spin or flat serves. Third, he's watching the ball, not your toss, and most peeps can't instantly change their minds in one split second.
You can toss 4 spots for your serves, and easily make it to Q levels.
You can toss less than 4 spots, and position your body under the ball where it is needed to hit the specific serve.....but dat takes a bit of practice, eh?
Since by the time you have enough practice to toss identically every toss, you ALREADY are good enough to NOT ask questions about your service toss.