I dont know, its between K Rool and Banjoo to me

Yeah, I can see Flygon working well on Charizard. The only thing that might not work is his bubble eyes. I thought about making an Ho-oh Zard to go with my Lugia too.
As for competitive battling goes, I much prefer to use my favorites even if that means I'll lose most of my matches. For me, it's just so much more satisfying to win with my favorites or original ideas than a team that was just copied from Smogon. I used to play netbattle during the 3rd gen all the time and I had a 75% win record just using my favorites so it isn't impossible.
Ho-oh and Flygon would be great aditions

I understand what you say, I always loved Mewtwo, even after those Ghost /Dark and Steel pokemon appeared -_-