some back of the envelope thoughts
if the return of the game without multipliers is R then it's pretty clear playing the 2x exclusively will give you a return of 2R, in other words the same return you would get playing the game on a ten play machine with no features
if you play 3x exclusively the multiplier comes every 2 hands giving a return of (3/2)R = 1.5 R. likewise the 4x return every 3 hands would be (4/3)R = 1.3 R and so on to 10x, (10/9)R = 1.1 R. higher multipliers give you greater variance at the cost of lower expected return.
so to get the highest return play 2x all the time; to try for the highest score play 10x and hope for the best.
i played one 100 game session each on each multiplier and was able to make 8000+ on all of them except 5 and 9 with the help of some timely big hands.
with the sound on you can play tunes on the multipliers. try this:
6 5 4 5 6 6 6, 5 5 5, 6 8 8, 6 5 4 5 6 6 6 6 5 5 6 5 4
or
4, 5 6, 4 6 4 6, 5, 6 7 7 6 5 7, 6, 7 8, 6 8 6 8, 7, 8 10 10 8 7 10, 8, 4 5 6 7 8 10
good mathematics
