Ice Beam is better on Starmie than Water gun to kill grass types and dragons.
Charizard can run a boosting move. It has the problem of having a physically oriented movepool while fire moves are special and a better Sp.Atk. It can go mixed something like:
-Dragon Dance / Swords Dance
evil Tyranitar, you don't want Heat wave if you already have flamethrower. And Waterfall < Surf, it simply has less base power and makes physical contact, which is detrimental against pokémon with static and poison point etc.
Blissey looks good. Minimize is considered cheap competitively but you can use it if you want. Otherwise, replace it with Heal Bell or Aromatherapy.
Gengar has the problem of being a Ghost type with no good atk stat. It doesn't have the Atk stat to really use Shadow Ball well. It is also too fragile to risk a hypnosis miss. Go with something like:
Giga Drain / Substitute
Dragonite is a great special attacker, a great physical attacker, and it can do mixed. It has many options, and Dragon Rage just sucks. 40HP damage is just very little. Outrage is only mildly more powerful than Dragon Claw but locks you in for a few turns. It's not worth the power boost from base 80 to base 90. As a special set, you can go with:
or a physical set
Salamence generally runs the second set better though, due to better Speed. Dragonite is better in the first set because it gets Thunderbolt to get better type coverage.
Master balls are the cheapest thing ever invented. It's more fun catching everything with balls that can fail. 'caught Latios in the wild without master ball ftw'