The yautja are shown to just pick a place to hunt, they seem to go for those that pose a fighting chance, but there is nothing that says they look at a planet and like use DBZ power level indicators to choose the most powerful place to hunt or anything cause even the original movies all contradict this. If we go by later content we learn there is even different groups of yautja who don't all seem to hunt the same way or have similar "honor" code like behavior.
As for targeting the Comanche, it seems more likely the pred is hunting the colonists as seen in the trailer. The remote nature of America wilderness at the time also provides much better hunting grounds than the idea of going against an organized army, cause if so then the first Predator movie made zero sense, why go after some random nobodies in the jungle as mentioned in the stories of the local girl Dutch and company find? Why not go after more trained and more dangerous war zones at the time that were around? The city hunter activities also make a zero lick of sense then when you think about it.
Later comics and novels tried to reason this stuff all out cause the logic of the hunting was a bit in disarray even. Predator 2 makes huge changes from what we saw in Predator 1. The Predators goes and makes things wild with yautja abducting people out of prison apparently even.
