Here's an idea that may be a stretch, but seems suited for the Rams' current defensive strengths.
First, what do we have? A class-of-the-league defensive line, solid linebackers, and a spotty secondary. Fisher plays a lot of Cover 3 and single-high because he hates giving up the run by keeping both safeties back. So let's call our defense what it is: a 4-4 stack (or often, 5-3), with one deep man and two corners.
Now, here's where it gets interesting. What if, instead of drafting safeties and corners for specific roles, we made the entire secondary interchangeable? Half our players already fit this hybrid role - think Trumaine Johnson, Cortland Finnegan, TJ McDonald - where they're often considered to be great candidates for potentially converting from corner to safety and back.
It's essentially adopting our defensive line coaching strategy, where the 2nd and 3rd string are treated less like backups and more like temporary relievers. Train up every member of the secondary like a starter at every position - outside corner, nickel, slot corner, deep safety, and strong safety - and change the scheme so that these positions are all interchangeable. With something like this, we could essentially play a man-up scheme, where assignments are given based on individual matchups, and the secondary's game plan becomes much easier: mix and match, figure out what works, and instead of trying to present novel coverage schemes or disguise shells, you're really disguising your matchups.
Tell me what you think!