Well, one punch man? Maybe you could read this http://www.mangago.me/read-manga/psyren/
http://www.mangago.me/read-manga/nurarihyon_no_mago/
haven't read boku no hero academia yet... ugh, too many in my waiting list.
my favourite is moonlight sculptor. i have a thing for similar type of protag too.
others i like:
- claymore
- one punch man (i feel SO MUCH for saitama.)
- mahou sensei negima (he's like super strong but he ends up being a provie teacher)
i think there's more but those are the ones i remember at the top of my head
Personally the only reason I sometimes get irked by overpowered MC's is when they make him ultra powerful without giving attention to the side squad. Some don't even give the side characters a proper character growth.
(Probably because of my childhood trauma watching bakugan where only the MC's bakugan thing evolved over and over again while the rest were left for shit. Same happened with digimon (at least the second lead got some importance here XD))
when there's a big cast i usually end up liking one of the MC's crew instead of him like in one piece and fairytail. i don't really mind tbh, but i do find manga/anime interesting when there's an OP side character
(haha. oh yeah. i do remember getting upset that my favourite in digimon did not even got stronger but not as bad as yours. HXH has the same disease too, now that's where i felt frustration. didn't watch bakugan tho, but i know it's on cartoon network)
I'm looking for manga that is like Boku no hero??? Like the protagonist proving himself worthy and the other character kinda looking down on him even though he is the strongest in the group. Much like Haikyuu but a supernatural/super power manga which is shounen