first... with Legendaries, don't rely on too many damaging attacks. its a Legendary, it can take a hit. ok...
Rayquaza ---> since its Spc.Atk is high, i would focus on Spc.Atk's like Dragon Pulse. sure, its a Power House, but what's the point of using Physical Attacks like Avalanche or Earthquake? replase them with something a little more worthwhile.
Blaziken ---> Hyper Beam and Fire Blast are good Spc.Atk's, but because of such a low PP and Accuracy, i wouldn't use them myself. i would teach it Flamethrower and Focus Blast. though, yes, Focus Blast has a low Accuracy, if you give Blaziken the Wide Lense, that will help a bit.
Groudon ---> well, Dragon Claw is a nice touch because of the fact that its a Physical Attack. i'm not sure about Eruption (i don't remember if its Physical or Special), but even though it has Drought, i don't know if i'd teach it Solar Beam. it has a very low Sp.Atk (even for a Normal Pokémon), and your only advantage to it would be if you were going against a Water Type because of Drought. maybe teach it Earthquake, Arial Ace, and Bulk Up (that way you can really max out its Attack, lol).
Salamence ---> i don't think i have to say anything about this one. seems good enough. lol
Tyranitar ---> seems good, but...that Thunder kind of erks me because it has a low Sp.Atk...i'd teach it Iron Tail, but thats just me. lol
Dragonite ---> ...full o' problems. its got a high Attak, not Sp.Atk, so...i'll put up a moveset i think might be better:
Fly
Dragon Claw
Thunder Wave
Giga Impact
that's what i think, but its my opinion, right?