Love the Replaymod and it works great for creating small clips with stable camera movement, however scrubbing through a bit of footage takes too much time, making cinematic, keyframe heavy renders take too long to finetune.
Being able to cache a small portion of the timeline would make this a lot easier.
I'm don't know anything about coding, so I don't know to what degree this is possible, but this problem really keeps me from using the replaymod for longer clips/cinematics.