I wholeheartedly agree with you about the "when it's good, it's really good" statement. The biggest issue I have with EDH is that when it's bad, it's miserable.
I second this. I used to have a regular playgroup in wich I'd play grouphug. Because we were missing one player, we played with a random guy which we didn't mind at first, but got really annoying later. I borrowed my friend's Mimeoplasm deck, and had him dead on turn 5 with commander damage, but I ddin't go for it because I didn't want to be rude, knock him out before he got a chance to do his cool thing. This turned out to be a mistake. What I din't think of was that if I knocked him out, he could have just found himself another game. Anyway, what happened later in the game that he manipulated both of my friends to go after me and leave him alone(he was playing control), while he himself was bricking on land. I thend again had an opportunity to knock someone out of the game(or kill their whole board, I can't remember), but again I didn't. However, I did make a deal with my friend that if I spared them and their board, they would stop swinging at me with thir flyers for one turn. I made him promise, which sounds kind of childish, but I really wanted to be sure. What happened next turn, he swung at me with his flyers nonetheless,bringing me down to 4, and then luckily topdecked meteor blast to finish me off. But the sad thing is,he didn't even win that game. He eventually got backstabbed by the control player, who had been manipulating him all game! When I talked to the control player after the game to ask him if he understood why I spared him on turn 5, he hust said "No, I don't. If it was you, I wouyld have just went for you."(Which I suppose is actually fair.) This whole game has kind of tilted me oof Commander for a while, as even when I play Grouphug with no win-conditions the table always punishes me for having a propaganda out.
Sorry about that rant, i guess I just had to get it out. To finish on a more positive note, I very much agree with Trainmaster. Canadian Highlander is dope. Let me just share with you one spicy story form the 2018 canadian Highlander championship hosted by LoadingReadyRun.
One of the players, Nick, is playing an artifact combo deck with Paradox Engine and Tolarian Academy called Paradox Academy against Adam, the other player who is on Mono-White Death and Taxes. Anyway, Nick goes off with inifite mana, and draws his whole deck with Staff of Domintation. From this point he has a number of wyas he can kill Adam. But then Adam has a response. In response to Nick drawing the last card of his deck he plays a Dismember which he drew off one of the Wheel-Effects, and dismember his own Thought-Knot Seer to make Nick deck! Luckily Nick, with his entire deck in his hand has the Pact of Negation to counter the Dismember, but wow! POWERFUL MAGIC, as the folks over at North 100 would say. You will probaly never find this sequene of plays anywhere else, and this is why CanLander is so awesome, and the folks over at Yellow Jacket are so passionate about this.