If they want to make hay while the sun shines and ride the pony to another championship they need to bring in a semi-experienced vet to backup Collaros. They were lucky he didn't miss any games this past season but chances are they won't be as lucky next season. Whether Zach misses 2 games or 6, a QB with previous CFL experience should be able to keep them in the hunt for a playoff spot while Zach recovers, maintaining a 50% record would be adequate. Strev. filled that role in 2019 when Nichols went down, hopefully they can find a known quantity good enough to manage the offence reasonably well instead of gambling on an unknown rookie to salvage their season.
I agree with this assessment 100%. Nobody unseating Collaros while he is healthy and a 3-Peat on the burner. Get a decent mid-tier vet QB to back him up because as you say lucky he did not get injured this season. 3rd string on the practice roster can be the up-and-comer if need be like Brown was/is. McGuire and Brown may get camp invites, but am sure there will be competition for sure as even in the little they did get to play, it left a TON to be desired even as an adequate backup.
TWO THUMBS down on the Dominique Davis idea. That ship has sailed.
Steveler maybe still comes back. After the NFL season his status on the practice roster down there could be toast. So lots of options available, but definitely need improvement at the backup QB role. Maybe McGuire is a world beater at practice for all I know, but that one game he did start he showed ZIPPO! 4 picks! That's pre-season ball for a pure rookie, not a two+ year vet on this team. Needed to show something/anything that game. Seemed like he could not read a defence for the life of him!

Brown....we have no clue. Really saw little action. Hopefully they will get to play pre-season games next year and be able to weed things out better with true live action and not just training camp practices.