Maybe there should be some hints in Punk hazard arc. We know that Vegapunk works with DF, implanted some of the pica pica powers in the original PX plus we know he made objects eat DF and even artificial DF like Kaido's with Momo.
The first guess would be strong marine df in a single px. See a PX with the 3 original admirals df would be dope yet even a bit strange (only BB should have what it takes to have more than a single DF), also in any case this is one case and I doubt Oda will introduce an army such as this.
But we also know that somewhat Vegapunk can create an artifical df most likely based on Kaido's df so he can maybe even use non marine df.. What if we have a PX with Kaido's abilities?
Also the old base for the PX was Kuma but what if he used another base, let's say that if the marines somewhat managed to take some WB cells at Marineford.. but Oda doesn't swing this way aka I can't see him making an army of WB looking guys but go for something way more original.
A good troll would be this base be Greenbull so that we see him and can start to guess his powers (other thing that Oda loves to do, make people guess) even before we actually see him. Also if I recall correctly he was said to be a "beast" so maybe a good start for another human weapon.
Maybe this can also be a good way to introduce a new ancient weapon aka Vegapunk somewhat managed to recreate the powers of one of these and put it in a cyborg or a guy. Example somebody who can control sea kings to an extent but since Oda can not do this (not orginal enough and no way to work on Shiraoshi) maybe a guy who can control weather or have some huge destruction power or whatever Oda see fits (and this will also be nice because instead of lifting some mystery about Vegapunk it will make it just more shrouded).
Another problem are numbers: will they be let's say 3, 7 like the orginal warlords or an army that can match a warlord or more but has strength in numbers to do so (example: 10 of these to match Boa)?
