I feel like I've been pretty lucky with encounters. I know I found Stufful within like three or four encounters, and Oranguru was the first thing I found in Lush Jungle, for example. But yeah, that does seem like kind of a weird decision. :/ Probably has to do with the small number of new Pokemon. They probably wanted it to be a bit of a challenge to get some of the new Pokemon. That's all I can think of, though. And I don't really care about how good Pokemon are for ingame. I'm just using Pokemon I like, and it's working out fine for me.
Right now, I've got a Brionne, Pikachu, Salandit, and Steenee.