One thing that I've constantly been discussing with people is having separate game plans for different types of opponents.
If you are rolling with someone much larger or stronger, there are certain moves that may not work.
If you are rolling with someone the same size as you or weaker, there are a whole new set of moves opened up for you.
Knowing both ideally is the goal, but if you could only master one, the first style/set of moves are the most important ones.
Marcelo Garcia Discusses this (addressing larger opponents) in the following video: