First off, tonights episode (ep 5) was amazing. One of the things ive noticed in this season is how different morty is. Hes actually standing up for himself and showing much more emotion. I dont necessarily think this is a bad thing.
Ive had a theory that Morty is actually going to turn into Evil Morty. Before you shoot me down, just think about it. Time travel is possible. The main rule of traveling in time is that you can never have contact with your original self (or change any huge factors in time/history). Evil Morty and our Morty has never met but Evil Morty is come in at one point after Rick and morty left.
This is were i also bring up the point of Mortys changing attitude towards Rick and the rest of his family. What if soon something just makes Morty snap? Will he turn aggressive and get away with Ricks portal gun and go on his own missions? Create his own gadgets and use the information he has collected from Rick against him?