I'm just gonna comment on the whole team cause I feel like it
Dragonite: Everythings fine, taking the advantage of STAB (Outrage + Fly). Replace Outrage with Dragon Claw if you can, power is 10 lower but it doesn't have any drawbacks (With Outrage you gotta use the same move 3 times + you got the chance to get confused after). One of the best overall stats in the game.
Tyranitar: Same with the above in my opinion, taking advantage of STAB (Crunch + Rock Slide), maybe replace Thrash with some status move (Bulk Up?). Probably best physical-damager, really high overall stats and sick attack.
Venusaur: Could replace Frenzy Plant or Razor Leaf with Sunny Day in order to get fast Solarbeams. Giga Drain/Synesthesis/Growth would be also great, anything between recovery + constant high damage (Giga Drain/Growth/Razor Leaf/Frenzy Plant for example) or sleep powder + bursting (Sunny Day/Solarbeam/Sleep Powder/Filler for example) is fine. Solarbeam kinda requires Sunny Day though (in my opinion), but Grass-type movesets are really hard to decide so I'm not gonna comment on that further. Probably best possible Grass-type.
Starmie: This is also good in my opinion, the extraordinary Water/Psychic -type makes it pretty awesome. Great advantage taken of STAB again (Psychic + Surf) and Thunderbolt for sure makes it superior against any other Water-type pokemon in 1v1. Lapras would be kinda great though, Water/Ice-type pokemon with really high overall stats, I recommend getting one.
Raichu: Thunder/Thunderbolt are fine, I would probably change Slam/Quick attack to Light Screen/Rain Dance (With Rain Dance, Thunders can't miss). Rain Dance isn't a must-have though, so saving one of Quick Attack/Slam is probably fine. Zapdos/Raikou/Jolteon would be better here though.
Your team still a Fire-type pokemon, Full-Psychic pokemon, and a real Fighting-type pokemon atleast. Here are few great pokemons that have the types you don't have at the moment:
Heracross - Bug/Fighting, high attack with really powerful Megahorn + Brick Break moves (it also has Reversal). Get Bulk-Up to make it even more powerful. Avoid Flying-types with Heracross, since Flying is 4x effective.
Arcanine/Ninetales/Moltres/Entei are all good Fire-type pokemons. Forget about Moltres/Entei if you dislike Legendary-pokemon. Moveset could be something like Flamethrower/Fire Blast/Confuse Ray or Will 'O Wisp/Sunny Day, for example.
Since you don't have the fighting-type yet, Blaziken, being a Fire/Fighting-type could be a great choice. Mixture of Fire- and Fighting-type moves + Statusmove (Like Bulk-Up) will make it pretty awesome.
One Full-Psychic could also be great. If you dislike Mewtwo, something like Alakazam with (Recover, Psychic, Calm Mind and maybe Shadow Ball/Safeguard) or Gengar with (Hypnosis, Dream Eater, Shadow Ball, Confuse Ray, Sludge Bomb (5 moves, pick 4 of 'em) ).
Since you don't have Poison/Ground-type, the male Nidoran that you can get by trading female Nidoran would be awesome.
Rate my team:
Zapdos level 73: Light Screen, Thunderbolt, Thunder, Drill Peck
Tyranitar level 73: Rock Slide, Crunch, Earthquake, Brick Break (Going to replace Brick Break with Bulk Up if I'm getting Heracross)
Charizard level 73: Dragon Claw, Fire Blast, Flamethrower, Fly
Lapras level 73: Surf, Hydro Pump, Ice Beam, Rain Dance (Confuse Ray would be kinda smart I guess, could replace Hydro Pump, Surf is kinda too good to pass I think)
Mewtwo level 73: Safeguard, Calm Mind, Recover, Psychic
6th pokemon at the moment is either Level 70 Victreebel (Sleep Powder, Growth, Solarbeam, Sunnyday)
or Level 61 Dragonite (Just leveled it up, gonna level further: Fly, Outrage (Dragon Claw already used), probably Ice Beam and Thunderbolt for the last 2 moves)
I'm not a professional with rating teams, this is just my point of view
