I read that one of the objetives is to:
"bug fixes to numerous aspects of the game,
including ones for custom maps. There are many more
bug fixes and balance changes than what is shown to the left, in which you can read the full list of changes..."
two weeks a go (video uploaded the 5 of september)
In this video the youtube user
Orange talks about the new maps (he did many competitive melee videos and also he reviewed all the maps of the first melee contest).
I didn´t see the whole video but
I saw the complete review of the new Blizzard map Swamped Temple
In the video, he explained some bugs like:
AOW creeping for merc camp was unbalanced (walking distances were not equal, called as spawn bug).
Platforms wood was with no simetry (north platform with wisp scout posibility, south platform with no wisp scout posibility).
Turtle level 10 eated his only bear, he chased it with a quimera and the bear was released in some island, he explained that he hated the map (in a funny way of course) because of that bug.
My point is that if in this thread the topic is to talk about balance the custom maps.
I sugest to watch his video (maybe he is not that serius but he do explain well many points of competitive melee play and balance)
hope this may help.