I get your pain, (although i 1shot Ryland and i kind of wish i didn't, i feel left out of how hard the fight apparently was), but what i do is just train 12-30 pokemon to max level. That way you always have options for beating any obstacle (helll yes its a grind, but its worth it). Also for the record 12 pokemon being changed as you progress should be PLENTY even though i have a full box of level 85 mons Imo nefing the leaders would ruin the fun for the people who like the challenge which is the main group of people this game is trying to target. Maybe Ryland should be nerfed but i cant talk about that since i got lucky (?)