What is your though about it?
I'm waiting until the Numbers are actually introduced. That'll be a big sign of what Oda intends for them.
-if they get individual introduction boxes like the Flying Six, Christ, Wano's going to last decades. That'll imply that at least some of the Numbers will have their own individual (small) plots, even if it's just as fights.
-if they get introduced collectively like the Oniwaninja's, they're probably not going to serve much more of a purpose than as background fighters against the Allaince, that exist to expand on Kaido's backstory more than anything
I think the second is most likely, but it can still go either way.
On thing that I am pretty certain of is that the Numbers are Kaido's allies (and family/tribe/race) and not actual members of the Beast Pirates. At some point in Wano we're going to get parallel volume covers, one of the Beast Pirates, one of the Strawhats. The Numbers won't be on the Beast Pirates one. That'll be Kaido, Calamities, Flying Six and his son.