This idea was born when i saw another blog, in which it was asked if Whiteberad's allis were at the same level of Marine's viceadmirals.
I think, actually, that all his allies are... weak. Not it absolute terms, of course, but they are very weak if confronted to Whitebeard himself, his division commanders, admirals, but also viceadmirals and shichibukai. For example they may be... as strong as Puzzle, the non-canon character from Ice Hunter Arc. Well, Puzzle was defeated in New World while these men weren't, so they are e little stronger, but I mean there are no big differences among them.
Here's my vision of New World hierarchies, which would support my opinion: when you enter in New World, you can be an indipendent crew or you can "become friend" of a Yonko. In the first case you'll go throught your way, but maybe you will be defeated by another crew or by the hostil environment of an island/the sea. In the second case it means that you are now under the wing of a yonko, and this will protect you from being attacked by another crew under the same Yonko's control. It's useless, obviously, against sea storms, sea monsters and strange islands (Urouge's or Apoo's ones for example).
When Whitebeard called his men in order to save Ace, in addiction to his properly men he called his allies... and that's for sure. The thing I want to say is that they went to Marineford even knowing they're too weak, because the man who asked their help has a big credit with them. That's why in the Marineford war we didn't see any great challenge between these allies and a shichibukai or a viceadmiral. They only helped in defeating simple marines. Luffy, in New World, will be right now stronger than them (ok, maybe not all of them).
Ace defeated Doma, and then he became allied with the old man; it's an example of "I defeat you in order to suggest you to become my friend".
Now I can use one sentence to explain my idea: Whitebeard's allies are actually noobs.
I hope you agree with me.