There is no direct line for a player to communicate with the devs. The communication goes through the CM team, who pass along the feedback. We have passed along all the comments about the quest UI, for example, from them being too bright and out of sync with the rest of the game, to the fact that some would prefer to see a rollback to the previous version.
Someone mentioned hotfixes --- that would not be done in a case like this, as hotfixes are reserved for when something isn't working and severely harms the gameplay (think of the AI change from the previous update as an example). The feedback being passed along does not necessarily mean that a rollback will be issued --- they've done the change for a reason so they will likely work on changing the aspects which players have said they do not like (brightness, font size, etc.) in which may they can apply their plans for the game with modifications from player feedback. But we cannot say what they plan on doing till they inform us. We have however stressed that everyone is in agreement they would prefer to see other things worked on first, things which have been requested for a long time. As we do with each report.
So if you wish to send comments to the devs, simply provide your feedback here and we'll ensure they're passed on. What we're trying to point out is that we can pass on comments such as you do not like the feature at all, you do not like certain parts of them for one reason or another, or you'd wish they worked on something else instead. We cannot pass on comments that the devs need to be replaced - that's a personal opinion and it is reviewed as well, but it's not feedback to the features themselves.
Change the developers...
