Heard one of the guys on GameXplain (Ash?) say they think Leon will be a fraud and I really hope that's the case, it'll be really interesting seeing how that would play out. I've seen some spec here + other places saying he'll end up being a bad guy, but that just feels way too fresh coming out of Sun and Moon with the Aether Foundation. Being a fraud isn't something we've really seen so I hope it's that, or something else we haven't seen.
Hop looks like the typical "friendly rival" which I know I, and a lot of others. don't care for. I would much prefer him to be a jerk, but outside of Blue, Silver and Barry, the rivals haven't been that memorable anyway, so whatever. The fact he's the champions younger brother could end up being very interesting though, especially if he is a fraud after all. Regardless, I just hope they don't go down the "Hop just beat Leon and now he's the champion" route again, it's way too cliche.