Last year I made something similar to this (viewtopic.php?f=150&t=88659) and also Medevenx (viewtopic.php?f=149&t=89896).
The idea is to agree on what IDs we should gave to the players that aren't in the game. Last year, some modders used my list (started at 4000), Slimm44 list (started at 8000) or Medvendex list (started at 2500 and used the empty slots from the 2K Roster).
This year I will use something similar to my list, but maybe starting from a lower number like 2700. I don't want to use slots between 2K IDs like Med did last year, because if any new 2K ID (a new player added to the game on updates) is released, than it may replace the ones we used, so we have to change the IDs again. I don't want that happening this year, so I will take a prudent distance from 2K IDs.
I'm still waiting for Steam to release the game, so hopefully I will have a list tonight.