I couldn't wear anything but the i4's honestly. They have such a small profile, and seem to fit just right. Everything else feels too bulky. That is just IMO.
Pod packs don't have crazy differences, but I use the proto 3+5. I LOVE it. Don't get any pod packs that don't have velcro along the whole strip(like Valken packs for example). The velcro rips off too easily, and they are a lot harder to tighten.
As for hoppers, yes it depends on your price range, but it also depends on what position(s) plan on playing. (That is if you are even playing on a tourny-ball, aka speedball field.) From what I have seen and experienced, Rotors are durable when it comes to the outer shell. They can take hard hits on the ground, but I see them jam up CONSTANTLY. I use the Empire Prophecy V2, and I've never had it jam on me...but at the same time I saw one get massacred from a bad dive into snake. So, it's all personal preference and gameplay. Both are extremely durable compared to the Halo and other cheap-o hoppers I've seen. Halos crack right at the neck, its inevitable.