When it comes to Mythic raiding, I feel the groups should be flexible like Normal and Heroic. I don’t see why it’s restricted to (20) players personally.
In my Guild when we raid on our fun run on Saturday’s we normally fill up the raid completely. This being (30) players. For our Heroic Teams, We fill up pretty full as well. We actually have multiple raid team’s due to the amount of interested raiders in my Guild.
I would love to see the (20) person restriction lifted for Mythic raids. Mostly because we can combine some of our raid teams for Mythic once we get more geared and may want to try it out.
One thing I would love to see however is the limit of players you may have for ALL difficulties raised back to (40) players like back in the day when (40) man raiding was a thing.
You wouldn’t need to fill it up with (40) players, But it would make more room for perspective raiders to join your team! 