The Replay Tracks are a mess and everyone knows it.
In my case, I was quite proud of my performance in Bear Trap campaign mission 6 and I wanted to make a video from replay. In the original play, I fired 2 AMRAAMs at 2 SU27s. Both hit and I could proceed with the mission. This is also clear in the saved TacView track. Upon replay, one of the missiles misses and the mission goes astray, the surviving SU27 making a turn and killing me one minute later.
So I strongly think that in the long term DCS should migrate from the current track system.
Short term, simple sanity checks should be added. Apart from inputs, the track should save major events that occured - object destruction being the most obvious. The record would mark that at 05:06:07.890 aircraft#1 is hit by missile#2. In replay, even if something goes wrong and the missile misses, the event should still occur. Ideally, simple (x,y,z) coordinates should be added as well for all objects at some time intervals (every x seconds) and the calculated positions from saved inputs should be checked against saved coordinates and adjusted if needed. This would fix the crashing bugs some players are experiencing.
Medium term, a separate TacView-like track should be recorded with more info for each aircraft.
Long term, hopefully, a balance could be found between the 2 methods, something that would work for the game's architecture but would also allow for the track to be played back and forth.