I'm looking for a manga where the main protagonist is confident in himself yet is still likable and doesn't make you wanna punch him in the face ^^
Im not looking for a specific genre
The only character I can think of right now is Ryouma from Prince Of Tennis

Hamatora Has a 2 season anime, you should watch them. The MC, Nice, is exactly what your looking for.
Also Mahouka Koukou no Rettousei, it has a different manga for each ark, but its originally a Novel. The anime has covered all the arcs, it's really good.

I personally think I would punch Ryouma in the face if I met him in real life, in manga for he's okay for likability, anyway, here are few:

Complete:

Hellsing (He's just too awesome, though not sure I'd like him real life)
Bambino! (I would actually like this guy in real life)

Ongoing:

Diamond no Ace (I would also like him in real life, though...there's a part where he loses his self-confidence)
Giant Killing (Would totally enjoy knowing this guy)
Kingdom (Confident but kinda simple, likable because of that)
Capeta (Would love knowing this guy)

So, by the end there my reccs became more of believing in self kind of confidence than what you seem to want.

Must Read Webcomic:
Unsounded

Lists:
Reading
Complete
Western Webcomics

Ive watched Hamatora the anime. In this case, his confident attitude is really funny, same with Diamond no Ace (i read the manga for this one)
And as for Mahouka Koukou no Rettousei (Novel) (which ive read the novel), Tetsuyas comfidence doesnt come off as arrogance

Ill definitely check out the others!!