Generally not a big fan of this mantle multiplying (except for GL kinda) I just tolerate it at this point, like really I feel it detracts from the significance of a character holding the mantle and I imagine it's somewhat confusing for the inuniverse characters who don't know their real identities.
I think he has a perfect costume to take on the "Scarlet Spider" moniker, and it would be an interesting change. It does kind of feel like Scarlet Spider is more of the unofficial "Robin" or "Nightwing" to Spider-Man.
I'm not against the idea of Miles having his own identity it's just that every time they've attempted to call him different, Spin or Spidey, it comes off as derivative or lazy. When you look at a character like Ben Riley, Spiderman was a stepping stone for his arc, not the other way around.
While I absolutely detest the idea of multiple Spider-Men swinging around simultaneously, I feel Miles has earned the mantle (even in a meta way) and renaming him, now, comes off as a demotion. Honestly, he should've just been left to be the one, and only Spider-Man of the Ultimate universe. (😉)