Your admiral equation is wrong.
1+.5 (# of admirals) doesnt work
heres what you have to use:
1.5^# of admirals.
the reason being that each admiral multiplies speed by 1.5 times its current speed.
1.5x=1 admiral, but having 2 doesnt give you 2x speed, it gives you 2.25x speed.
using this equation, you should be able to go 100x speed with only 13 admirals. The problem is, the devs made sure this didnt happen by making admiral abilities do less after a few. They dont want exponentially increasing speeds with stacked admirals because people will abuse it. You may have noticed your 1+.5 (admirals) doesnt work. With that formula, 20 will only make it go 11x speed.
AND THIS IS MY 100TH POST. CHEERS!