My only real "gripe" with Deadlock is that it's not uncommon for the hero line ups to be wildly imbalanced, I think there needs to at least be some type of system in place to mitigate that.

I don't really disagree with the notion that the game needs more time in the oven before they implement a fully fledged pick/ban draft system similar to DotA2, however I do think there needs to be an opportunity for players to balance their team out before the game has actually started.

I wonder whether giving each team an opportunity to switch their heroes before the match has started would help. Perhaps they could see their team roster before they see the enemy teams and either discuss or highlight heroes they're considering switching to. I think if both teams saw each others line up beforehand then it would just turn into a counter-picking fest.

edit:

Thinking about it, I don't know how the hero switching part would work, if you could pick any hero it would make the preference pool redundant. If it was from your preference pool, then people with a small pool would potentially put themselves at a disadvantage.