Sometimes you just want to play casual and check out the game, but if you select the “all maps option” you could still get the chance to get a competitive/standard map. So theres still little chances to check out all the new stuff DE will have to offer.
An “uncommon maps” section with only non-standard/competive maps will be welcomed, as you will get the chance to see all those interesting maps that even thou are no fit for tournaments and rankings, they are still fun to play.