Snapshot "Reset" points (or "save" points) is an effective way to do this. But it's difficult to analyse a full-blown simulation like this one to determine *which* variables in the simulation code must be in the snapshot. Saving the entire simulation state is usually prohibitively large. But, as a minimum, you have to save every state variable that will be used in the computation of the next simulation frame. This usually consists of global variables (but not all), and some local variables as well.
This is usually small enough to take a snapshot every few minutes or so. These reset snapshots along with the recorded interactions (switch hits, control inputs, etc) that ED already records could allow you to reset to another time forward or backward that you have a snapshot for, and then play the interactions from that point forward into the simulation.
If you have ever looked at X-Plane, Austin Meyers and his crew have an excellent playback feature that actually has a slider that you can drag backwards or forwards to any previous point in your current flight and continue the simulation from that point. But X-Plane is just simulating your own plane plus maybe a couple of extra flight models. The DCS sims are simulating your ownship plus possibly a full threat environment complete with threat platforms, weapons, radiators, and countermeasures. That's a *lot* of data to analyse.
This is a good topic for the wish list. I'm sure ED is currently concentrating all of their resources on completing the efforts for release. But it would sure be nice. It's great fun to play back your missions and see what *really* happened. Right now, you have to fire up a track, and then carefully use cntr-Z to speed things up to get to the action part. But not too fast or things will get out of sync. Reset and playback is a valuable part of the simulation experience both for "training" simulators and "study" sims like ours.
Maybe ED will consider this after the simulation is "release" ready.