I feel one of the biggest mistakes they made with it is that you can't learn new moves upon levelling up. With evolution you can just do it next level, but if you miss out on a move... that's it. Gone. Unless there's another means to get old moves back (I haven't checked yet) but if it's anything like needing to find heart scales like in the 3rd gen games it won't be easy.
Otherwise I like it. I always wanted a kangaskhan but was never able to catch one in any generation. I'll be using it mostly to catch unusual pokemon not found in SS.