Why not improve non-used champions for pro lvl play

All these buffs and nerfs and what have you and this talk about balences champion... you want to balance league? well leave these common champs alone and how about you change or buff other champs so there is a bigger champion pool for pro's. example. you got 120+ champs now. like nocturn for example. but these champs are worthless in the "league". when you see higher elo matches and lcs your lucky if you get to see maybe 12 different champs.. thats bs. why cant a champ like nocturn be in there.. why? because you wont fix these champs so that they can be played at a proffesional lvl. it gets old watching the same 15 champions every damn match.