If this is not the correct place to be submitting these questions, please direct me to the right place.

My question is: Since the Commander variant is not "officially" Magic the Gathering rules, to whom do we talk to about Commander specific rulings? Players argue about Commander specific game rules and/or abilities.

Eminence, for example, how is that not a game breaking mechanic? Since the Commander in the Command Zone cannot be targeted, there is no way to stop the Eminence ability unless you use an Instant that counter target triggered ability, for example (since you are targeting the ability on the Stack). But beyond that? The only thing comparable is Planeswalker Emblems. But Planeswalkers have to be built up in Loyalty counters to the point where you have enough Loyalty counters to PLAY that Emblem. The Emblem does start the game in the Command Zone.

The other issue is Commander Ninjitsu. This allows the player to cast the Commander from the Command Zone rather than from the hand (as with normal Ninjitsu) if an unblocked creature does damage to a player. But because it is an activated ability, the argument is that the cost stays the same.

So my Commander costs 1 to cast. My opponent's Ninjitsu Commander costs 1UB but has a Ninjitsu cost of UB. Both are on the battlefield and both are destroyed and returned to the Command Zone three times. So in order to cast MY Commander a fourth time, it will cost me 7 (1+2+2+2). But the Ninjitsu Commander still only costs UB? Why does the Ninjitsu cost not go up? Because it is an activated ability? How is that fair? Yes, Ninjitsu is an activated ability. But because it is the Commander, would that not alter the ability?