15/8 makes sense to me. If you play "safe" instead, you will not win as often when you hit your opponent and you will lose more races where no hits happen.
I would likely pick the same play here before seeing the bot info for the 1st position. With this info at hand, I break my 5pt because you are less likely to win the race and in the variant, your hits are stronger on average due to the absence of home-board blot.