I've been asked so I will make a top 10 list based on recent activity of what I have seen in public games and premades. With all these lists, its just someone's opinion, so no offence is meant by it. The five categories I'll use to grade people out of 10 are -> Micro, Game Sense, Teamplay, Awareness and strat variety. I'll expand on these categories here:
Literally self explanatory. How you control your army, your elites and your heroes? Using concaves, using several control groups and splitting your army.
The knowledge of the game. This is beyond knowing the counters. But when to engage, when to drop, guessing who has a hero etc. In addition, the understanding of knowing what to do, early game (elite meta?), mid game (who to fight?), and late game (SD play and late game hero/elites)
A category that in my opinion is least explored in MA. After all, its a team game, so its not how strong an individual, but how strong the team is. This includes, syncing your elite, hero and merc choice with your ally. Engaging together. Helping your ally farm.
Spotting that ghost, seeing those crawlers, reacting to a drop. When MA gets frantic, have you got the awareness to notice when you are getting backed?
With some counters still working in the game, mixing it up ca be good. If you get predictable, a player/team can alter their gameplay to hard counter you aka "get meta gamed".