It's a very simple problem:
The MC, despite being newly turned and comparably weak, can control a very old, very powerful vampire.
It doesn't, therefore, matter how weak or young the MC is.
Him being weak is irrelevant, if he can control the strongest around.
He has access to all the strength that any vampire has, by proxy.
This is why the analogy with Superman was presented.
He needs ever more powerful enemies, to be a threat to him.
If the MC is able to overpower and use any vamp he wants, he is not ever placed under threat.
His power automatically enables him to overcome any situation.
If the hero is never placed in situations where he has potential for loss, never under threat, then he's not much of a hero.
The whole point of being a hero, is that you will undertake the task with the threat looming large.
No threat, no hero required.
Umm, I think you kinda missed the point of Superman. Love is his greatest strength.
Without that love, for the planet & its people, why would he be a hero to them?
Green kryptonite & red suns might argue about being a more impactful weakness.
Of course Superman "is shown all powerful" that's the whole point.
Because he's too powerful, he had no viable enemy.
Lex Luthor, really? Pah. Supes could destroy him with a blink.
No real enemy.
Brainiac? OK, another enemy who can't match Supes for physical, so has to be highly intelligent, to be able to out-think him.
No enemy who can harm the protagonist = no threat.
No threat = no hero.
This is where the problem comes if you make your protagonist invincible.
The antagonist is neutered by that & must become ever more powerful, to present a threat to the hero.
Hence Doomsday.
I do not think that the Mafia/Camorra/'Ndrangheta, etc. would use uber to pick up the daughter of the don.
I think they (maybe?) use drivers/people that they know & trust?
I don't see any reason to view this underworld society any differently.
