As my time has exceeded 200 hours, I've realized: Never have a strategy or a specific play style. Each opponent is different and must be dealt with in different ways. You have to be adaptive and know what to do based on the skill level of your opponent. Within a few moments, you should be able to know whether it will be an easy victory or if you will struggle just to stay alive.
Good example: I was playing a Ninjara in Party Crash. I was going to lose because I couldn't get close with my normal defensive play style. I was compromised; I had been figured out and I knew it. This realization happened fast and I had to change fast. So I rushed the Ninjara in a very aggressive manner and he wasn't prepared. My style had suddenly changed and I won the match. Had I kept playing safely and kept my distance, I was going to lose.
That particular tactic actually works well against people that use Ninjara. They know that you know that they have that teleport move and they expect you to be careful. But if you are not careful and play aggressively against Ninjara, you can counter almost every one of his teleport grab-spams.
A very useful skill is to not always throw both of your arms. Punch with one, and keep the other held back. You then have the ability to always punch through a grab. I've noticed that lower skilled players are always throwing both arms; this leaves them in a state that is easy to punish.
There is a shocking, absurd and ridiculous amount of strategy in this game. I haven't yet sat down and gone through all the arms' characteristics, but I think I would benefit from old-school analysis. Can you write down on paper, from memory, each arm? Do you know, from memory, the effect and weight of each arm? This is what a true pro probably knows without hesitation. I can't dedicate that kind of time, due to my job, but I do fairly well online nevertheless.