Sorry everyone - my schedule hasn't improved much lately and it's been chaotic.
If a player is not placed on I.R. and is only expected to miss a couple weeks, I generally will keep him as the starter if they're the team's starter when healthy. I went ahead and made Jacoby Brisset the starter a few days ago on the roster only because Luck had a set back in his recovery. When Andrew returns then I will add him back.
There are a handful of players that have been in the league for 1 to 2 years but aren't in the game. If those players are added to main rosters, I will typically find someone of their exact same body appearance general weight/height and overwrite them in order to maintain the years of experience. If you create that player it will show them as a rookie even though they've been in the league for a year or so. It's just a detail thing and I'm probably a little O.C.D. about it but that's why I choose to over write some and create others.
As for right now I will stick with my current base set and keep going with it. Especially since several players originally on I.R. are set to return in the next week or so. It will be a quick addition back to the roster instead of waiting for EA to release the official I.R. status.