well they're definetly still in the training process.
Tyranitar LV67
crunch
earthquake
surf
rock slide
Here's a standard one: Crunch, T-bolt, Focus Punch, Substitute. The hold item should be Leftovers.
Or you can use the special Tyranitar. Modest nature, hold item: Lefties again. EVs: 252 HP, let's say... 68 Speed, 190 sp.attack. Moveset: Crunch, T-bolt, HP Psychic, Flamethrower/Ice Beam
Scizor LV47
swords dance
iron defense
false swipe
slash
How about to use him as a BP-er (Baton Passer)? Nature: Impish, Careful. Hold item: Leftovers or maybe Liechi Berry. EVs... I don't know. at least 198 speed and you can decide the other ones. Moveset: Switch False Swipe to Baton Pass and Slash to either HP Bug/Rock or Silver Wind.
Arcanine LV34
bite
flamethrower
flame wheel
take down
Don't use 2 attacks of the same type. Use only Flamethrower or switch F-thrower to Overheat. Take Down can be replaced by Extremespeed, because Extremespeed always strikes first and has a much better accuracy. He will learn that move on lv... 49 if I remember right. Bite can be replaced by HP Fighting/Grass and switch Flame Wheel to either Sub(if you got HP Grass) or Howl to boost both HP Fighting and Extremespeed.
Almost forgot about the hold item! Give it Leftovers since I don't see any other possible good hold items for him.
Mewtwo LV79
swift
recover
rock smash
psychic
Giving Rock Smash to Mewtwo wasn't a very good decision I think. Anyway, take out R-smash with Move Deleter and give it Calm Mind instead. Swift can be replaced and should be replaced (because Mewtwo's spa>attack stat) by either T-bolt/Flamethrower/Ice Beam or any special condition moves like Safeguard. Hold item: I suggest Leftovers again.
Aerodactyl LV5 lol
wing attack
fly
Won't comment here too much...
Aerodactyl@Choice Band
HP Flying/Aerial Ace
Rock Slide/Ancient Power
Earthquake
Double Edge/Return
Heracross LV25
horn attack
endure
fury attack
brick break
Nature: Adamant. Hold item: Salac. Moveset: Rock Slide, Megahorn, Swords Dance, Brick Break/Focus Punch. Or you can give it Choice Band, but remember to give it only physical attacks then, because Swords Dance won't have any effect in that case.