Well, Rivers has his best shot this year so he'll get his chance. This roster is super young, he has a max of next year then a replacement would still have to be found. If he's ripping it effectively deep into the playoffs he'll likely come back. If we're one and done, with this championship level D and OLine, if they can find a more promising option they should and will.
My two concerns for this team would be having no DE pass rush of significance and having no dynamic production from the TE spot to exploit that middle space, which in theory should open up the running game better. We seem to have JAG’s at TE. We need a Dallas Clark, Kelce, Kittle, Ertz or even a Waller maybe. We have nothing close to where these guys have been. But I think having consistently no pass rush is going to be the downfall of this team into the playoffs because the QB’s get better and those teams will exploit the weak zones of the defense because they know they have a certain amount of time against the Colts.