I did the same thing in the past, as I have two 12V DeWalt Ni-Cd drills which are both near-new, but all of the batteries are toast. When the last of the batteries failed, I bought a corded store-brand drill and used it on the rare occasions I needed it.
Then came time to replace flooring during renos at my last house, and I went on a subfloor-screwing rampage to get rid of squeaks. Dragging the cord around would have been a pain, so I bought a DeWalt 20V impact driver and drill combo. They were worth it for that one project alone, and are still going strong while being used semi-regularly for miscellaneous purposes around the house. I had never used an impact driver before, and was astounded at how well they keep the bit in the screw head (Robertson or Torx).
The corded drill got relegated to hard use jobs, such as mixing floor levelling compound and grout.
Moral of the story - your plan makes sense, but:
1) Get a drill with a clutch (corded or not) if you need it for driving fasteners which are prone to over-torquing;
2) Consider a combo with an impact driver if you hate it as much as I do when a standard drill makes a Philips-head bit cam out;
3) Think about whether dragging a cord around is worth the cost savings associated with battery replacement.
Also, it looks like Ridgid tools still offer a lifetime battery warranty if you register (free) within 90 days of purchase:
https://www.ridgid.com/us/en/3-year-limited-warranty