It is not possible to identify one bot to be profitable as its ratio keeps on changing every time. One bot is profitable on one turn in the next turn it may end up in loss.
Considering above I will see which bot or bots are giving best profits in the round and will invest accordingly in two three or more bots.
Further, it also depends on my bid amount. If I want to place bid of higher value, I may ignore bots whose voting power is too low.
I will select the bots who have the good paying ratio
Who automatically refund the invalid amount.
I will also prefer the bots who support some funding projects.