"I mean, it is excessively sport-oriented: you cannot put your hands on the opponent's face, you cannot kick nor hit him, etc..."
Sport-oriented or Street-practical.Anything you learn, it should be for self-defense and not for amplifying violence(it seems like you just want to hit people just because you can:) or maybe I'm misunderstood)
Anyway, coming to what you need to choose in order to achieve a street-practical confidence as well as trained in a way to get out of any situation.
For ex: half-a-dozen-to-more opponents with weapons with anger with big biceps
One skinny guy pointing a gun right behind your skull.(I'm serious!)
You should go for Krav-maga.
Its for anyone and everyone.It a self-defense system and anyone could need it.
Kids too young (under 13,but it differs) should not do this because the safety gear would not be appropriate for their body-size and the training is quite intense.
Its not a martial art and its not as much sporty as y'know karate, wing chun, judo , aikido etc.
But, it will train you to stand alone and disable your opponents in the least possible time.It can be dangerous for the receiver(one who you target) because it consists of moves which target all areas of your body.
It teaches you to use your attacker's force against him/her.
It trains you mentally to defend and counter-attack at the same time.
Get a good book on Krav-maga such as 230 self defense tehniques in krav-maga(I think that's what it is named) but i recommend you join your nearest Krav maga institute because you are supposed to train around people to learn better.
for ex: They are going to literally make you stand in the middle of a room while 3-4 opponents(your fellow training mates) will create a situation of total stress.
(With careful supervision,of course)
Long story short, if you really want to feel safe walking on the streets or any place where people might try to steal, stab or bully you, krav-maga is what you need to approach.
Also, brazilian jujitsu can be quite sporty and very much street-realistic, or so I've heard.
A little History:
"In the mid-1930s, anti-Semitic riots began to threaten the Jews of Bratislava, Czechoslovakia. (The country was created from parts of Austro-Hungary in 1918- a result of World War l) Lichtenfeld became the leader of a group of Jewish boxers and wrestlers who took to the streets to defend Jewish neighborhoods against the growing numbers of national socialist party and anti-Semitic thugs. Lichtenfeld quickly discovered, however, that actual fighting was very different from competition fighting, and although boxing and wrestling were good sports, they were not always practical for the aggressive and brutal nature of street combat. It was then that he started to re-evaluate his ideas about fighting and started developing the skills and techniques that would eventually become Krav Maga. Having become a thorn in the side of the equally anti-Semitic local authorities, Lichtenfeld left his home, family and friends in 1940 on the last refugee ship to escape Europe."
Know that whatever you choose within martial arts or any self-defense training,
do it for the love of knowledge and to provide defense for you, your family and anyone else who need it.
Ps: If you Combine brazilian jujitsu + krav maga + taek-won-do + wing chun + kick boxing.
You will be A-mae-zinga!
All the best!