First, Pokemon always rounds down. Thus, 126 EVs in a stat gives you the same boost as 124 EVs. If you have 126 EVs in two stats, it's slightly wasteful, as it's better to put 124 in a stat and 128 in the other.
Goodra: Nobody uses grass attacks on Goodra. Attempting to switch into a grass attack would only boost physical attack, which your Goodra doesn't use and only serves to increase damage from foul play. Replace sap sipper with gooey. Replace dragon fang with choice specs, because choice specs powers up everything and gives more power than dragon fang. Without healing moves, you're not going to keep Goodra on the field very much, so the choice locking shouldn't be too bothersome. At base 80 speed, it won't outspeed very much. You're better off maxing out HP and giving it modest nature. Having two attacks of the same type is often considered a waste. Replace dragon pulse with sludge bomb to cover fairy.
Kingdra: First, replace mystic water with lum berry so outrage doesn't confuse you on its first use. It would be much more powerful if you invested in one attack stat. I suggest going for physical, because it gets dragon dance and better physical attacks. Give it 4 HP/252 Atk/252 Spe Jolly. Replace draco meteor and hydro pump with dragon dance (to be able to outspeed a lot more Pokemon) and iron head (for full weakness coverage).
Sceptile: Sceptile isn't allowed on dragon teams, because it can't be dragon type until after the battle starts. I suggest replacing it with Dragonite, since you seem to already have enough tanks.
Dragonite @ Lum Berry
Ability: Multiscale
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
-Dragon Dance
-Outrage
-Iron Head
-Extreme Speed
Lum berry helps prevent poison and burn from breaking multiscale, as well as allowing it to use outrage once without getting confused (but not both). Dragon dance sets up Dragonite for a sweep. Outrage is its main STAB attack, though it should only be used after fairy types and steel types are removed. Iron head gives full weakness coverage, and extreme speed prevents priority attackers from ending a sweep.
Kyurem: Two-turn moves are usually bad, as it gives the foe a turn to switch or set up. Replace it with fusion bolt to hit steel types and water types better. Draco meteor isn't going to do much, as it has a jolly nature and another dragon attack. Replace it with iron head to cover rock and fairy.
