Something to note that might not be relevant for everyone depending on your job/social obligations: given that etf2l plays 2 maps per official instead of 1 like RGL does, officials might eat up a lot of time. Again, this may be fine for some of you, but I do not think that everyone who plays competitive tf2 is committed enough to sit through a potentially two and a half hour official. Add a potential warmup game to that and you are essentially gaming for three and a half hours, which is a much larger time commitment than the 30 mins x 2 that came before.
I think if etf2l wants to implement this change, we should follow the RGL format of only playing one map per official. This relates more to the "casual" competitive tf2 player who plays the game for fun than the average prem gamer, but ultimately it is the former that keeps the league alive, not the latter.