I think it said that when the title evolved some chakra (yin) emerged from his eyes to solidify his experiences as a title ... From which I guess this title system is more of his Earle emergence of his mangekyou ability like with obito with the rock crushing him (I think)

You didn't read far enough, some of your points are incorrect as they were shown later in the story. Stop here I'd you want to avoid spoilers. The reason he doesn't have the Sharingan is because he used the chakra meant to awaken them as a sacrifice help strengthen his body. It may seem stupid at first glance but he's punched a tailed-beast bomb and tore apart a susanoo with his bare hands. And damn I forgot what else there was I'll have to make another comment.

Ahh yes, as for ninjutsu he can use ninjutsu. It's just usually unnecessary for him since his taijutsu can typically handle whatever he faces.

Mc no tiene hermanos, obtener Sharingan por si solo no es tan bueno como el Mangekyou, y eso se terminan agotando fácilmente, entonces, enfocarse en el Taijutsu está bien, especialmente, porque mc no abandonó el ninjutsu de ninguna manera, solo abandonó el Sharingan.

So why did he choose the uchiha? Because or uzumaki or senju would be better

It is still kind of stupid sure he is superhuman in body strength but what about the unique supernatural power front the sharingan?

Stop here if you don't want spoilers. He gets sharingan later on.

well, i havent read the ff yet but im a bigfan of naruto if this is what you are worried about it should be fine as long as the author is smart, if mc is strong then he can just take other peoples sharingan like danzo so shouldnt be a problem