getting black 10 times out of 11
The system will give the player more due black, the one more out of 50/50 alignment, the color, with the exception of previously playing each other where it alternates.
For bullet you've been white 208 times and black 212
For rapid 144 white, 130 black
For blitz you're exactly even
In any color allocation method, you can still see strings of the same color. Aborting because of getting black isn't likely going to help much and will more likely put you in the poor sportsmanship pool.