There isn't a place for mission issues in the discussion boards as far as I'm aware (if there is please direct me to it), so I'm hoping this is the right board.
I just saw the missions and I get it, to some degree. But to require 5 man pre-mades is ridiculous. It's hard enough for me to get a 5 man pre-made going, and I'm sure others are in this boat as well. Some are worse off, and don't have that many friends on at one time. And the difficulty besides, you've done a good job to make a challenging map, but do you honestly expect every player to have 5 friends on at a time-- all of whom are good enough to win with the challenges you impose?
This needs to be toned down. It's going to be a nightmare for me, impossible for a lot of others. Please don't require 5 man pre-mades, it's a bad idea.
So, I tried a few more times but ultimately wasn't able to get friends together for the pre-made missions. Furthermore, as I'd been dealing with a bout of depression, I was playing League just to focus on something else. I couldn't even get the solo missions done because, despite being paired up with diamonds for most of my tries, we kept failing. No one stayed together, everyone wiped just before the boss. It was too frustrating; and I wasn't ready to deal with more of said frustration and the associated pressure I place on myself to complete the missions - so I didn't, I stopped playing that game mode.
So, ultimately: I stand behind everything I have said. Too much was asked of most players. Honestly, I was excited for the star guardian event, even bought a couple of skins (I'll buy the Syndra skin next, when I can). But the missions kind of killed it for me.
With the way they have made me feel, I'd be okay if missions just went away forever. I'd rather feel energized for big events and releases, not pressured.