I am at level 421. I never tried using the skill of Command. So I resorted everything in my skills and added several levels of Command, but it did not seem to do anything. Did I miss anything, or does Command just not do much ?
Command is typically the taunt skill of a wizard 
Lures the mobs to the big minion you are controlling.
you cannot gain any benefits from putting hero points in command if your OH does not have command as a special skill(either because it’s a tome or you amber-ed it). Command heals your minions and taunts the mobs into attacking your defensive spirit(which is the big floating armor dude). It will only take effect when you cast it(meaning you tapped/clicked/keypressed/buttonpressed or whatever kind of action you do to activate or cast a skill depending on your device controls).
PS. i’m not aware though if there is a proc or something like that for command in 2.1
Well, looking in Command and seeing that it appeared that it would add an increasing amount of damage to every hit (depending on how many points you add to it), I thought it would be an awesome thing to have. Now, not so much. Thank you for the feedback.
Command heals minions hp by 10% and taunt enemies by 10%.
It can be got from tome or by using amber crystal on a oh. This means you can have manashield with command or orb with timewarp or even vial with torrent.