What i am looking for is pretty much thishttp://www.mangaupdates.com/series.html?id=71967 or this http://www.mangaupdates.com/series.html?id=19104 , namely a protagonist that hides either his abilities or his identity (or both) for specific reasons. This leads to them being underestimated or even being frowned upon. In the end, these type of animes and mangas have the most "hell yeah" moments for me.
Genre is not that important (sports for example) but i rather avoid Shoujo in this context, though Dengeki Daisy for example is amazing.
Other examples i have already read:
Eyeshield 21
Dengeki Daisy
1/2 Prince
Legend of the legendary heroes
Dendrobates (pretty much exactly what i am looking for)

The recommendations can also include the "crouching moron, hidden badass" stereotype, i am not too inclined to Gender Benders though

Zennou no Noa

in need of romance?
uncommon, sad, sweet

how about Mx0? although it has a rushed/axed ending.
Full Metal Panic!
Black Cat not sure that this would count.
Bloody Monday
Tower of God

as for Mahouka Koukou no Rettousei, i can only recommend to read the "Novel" since the manga version is...simply lacking. some conversations(the kind of conversation that are important to understand character like Saegusa Mayumi and how the Main character Tatsuya views them) havn't even appeared and the magic law hasn't been throughly explained...
...Chrome Shelled Regios is pretty much the same

Noblesse Completly fits your description, especially "hell yeah" moments. Dont let the starting turns you off.

[img]http://media.tumblr.com/e43f35cfdd762cc666571a6dd0f163d5/tumblr_inline_mhbel8Cy8V1qz4rgp.gif[/img]

Quote from strixflash

Noblesse Completly fits your description, especially "hell yeah" moments. Dont let the starting turns you off.

I totally agree with you. It turned me off the first time. Afterwards when I had nothing left to read, I went back and looked through it and I found out WOW! THIS IS AMAZING! I couldn't believe that I had let myself drop Noblesse before.

maybe this will help

or this

or this

My personal favs are
Rurouni Kenshin
Trigun
Id
The God of High School
Sword Art Online anime?

other:
Isekai no Seikishi Monogatari anime
Hagure Yuusha no Estetica anime

[img]http://s2.postimage.org/hmf63ku61/Nice_Scenery.jpg[/img]

I feel likedurara! might fit.

Listen here
Livin just to keep from dyin
[img]http://imagegen.last.fm/TheDarkTen/recenttracks/imgooley.gif[/img]

Ouroboros might fit

Highly recommend the legendary moonlight sculptor
The main is a game based character that showily builds up strength, hiding his normal identity from the world as he gets more famous, doing unbelievable quests. The main has a corrupt personality who only find value in money and will do anything to make it. It's a very interesting novel, which I rate very highly.

Moonlight sculptor is a novel with a slow start but definitely worth the read

you should definitely read Black Haze, it starts off pretty slow but after the first chapters it gets really good, and has plenty of those "Hell Yeah" moments. i love you rood!!!! 😛

[img]http://24.media.tumblr.com/3b280fafb72cad0f718be64368e64ca7/tumblr_myylzmuiY41rw3pzao4_250.gif[/img]
Like educational manga? take a look at Ed U. Manga's list of manga here