Hi everyone , this is my first post . First of all this game is incredible . Difficulty is much much more than im used to ,and every gym battle was interesting. I was never min/maxing in pokemon games cause i never needed to. Now after i beat terra after ~15 tries im left with 3 of my pokemons overleveled which is gonna be a problem in next gym/boss fight. I need help with my team. 
Noivern(ev trained in spc. Atk and spc.Def ( iv 31 for spc.Atk and 30 for spc.Def)) level 78 
 Dragon pulse 
 roost 
 Boomburst 
 huriccane 
Noivern( second one without ev training) level 71 
 dragon pulse 
 superfang 
 roost 
 huriccane 
Jolteon(no ev training) level 73 
 Thunder wave 
 Discharge 
 thunder 
 some weak bug-move 
Nidoking(no ev training) level 78 
 surf 
 earth power 
 sludge wave 
 flamethrower 
Charizard(no ev training) level 78 
 Fire blitz 
 heat wave 
 flamethrower 
 firespin 
I am currently catching Beldum over and over to get good IV's on him and will EV train him afterwards. 
P.S. English isn't my native language so plz , have that in mind. Sorry for any grammar mistakes.