What Riot should learn from Odyssey's missions and feedback
Pretty much every thread about Odyssey has been a complaint from players who don't want to do particular missions about players who do. What Riot should take away from that is there should never be missions that require every player to do something besides being on the same difficulty. All it does is make the missions far harder than they have any reason to be. (while having separate queues for particular missions would also work, that's far more difficult for all involved than just making the missions reasonable in the first place)
I for one am a bit surprised they didn't realize this around the same time they realized it's uncool to require everyone to equip an event icon to get event rewards. But oh well.
Hopefully they learn from this that making everyone take the same summoners/champions/etc. makes people not want to play the game mode.