Seriously, Im not one for matchup porn but....:
- 10 Strawhats (assuming no more recruits)
- Shanks + 9 Commanders = 10 (sure theres Rockstar but hes not a commander)
- 9 VAs plus Kizaru = 10
- Akainu, 2 Admirals (Fuji/Ryo), 7 Zodiac VAs = 10
The only obvious exceptions to this are Blackbeard and Imu. Blackbeard has his 10 commanders, but Im not sure if Aokiji will end up fighting Luffy or just Koby otherwise (i.e. not counted towards a direct matchup with the crew).
Then Imu has 5 Gorosei and what "seems" to be 9 God Knights, but I think itll be 10 to equate the 16 motif the WG has. Then again I think this faction has to be bigger by default considering their potential endgame status so RA's and other allies will help. Then theres people like Kong too still.
So all in all you have what seems to be 4 factions, like Luffy, with 10ish main members. It does make you hope that Oda will give everyone fights (even though itll never happen ever).