This brings back memories of the great debate about the Vinsmokes lol.
I love them actually.
I think so many underestimate them.
And I think they were victims of Oda fast pacing through their fighting skills/combat (skipping)
Which he clearly is showing the same with even the likes of Oden. Where we never really got to see Oden go all out. As Oda skips LOTS of combat for many characters.
But Vinsmoke being a shield for Capone's body for a good chunk of time between SO MANY Big Mom pirates speaks for their abilities and strength. Sure, not Yonko commander level, but Veteran level sounds perfect, or a bridge between Veteran and Commander level is even more fit