I've just checked the Nextgen Composer in 8.0, and I wonder about the usage of screen real estate.
To me it looks like I zoom to 150% - which is great for ergonomics, but now many things that fit onto one screen in the old composer now make a scrollbar necessary.
It is hard to get an overview, because you have to scan the whole screen for information. I can't see how that makes developing faster.
Is it supposed to be that way or will there be a compacted version?
In service editing, switching through service info, input, output, services etc takes more time due to the animation, in the old version you click the tab and it's there.
The tooltips on the toolbar are missing yet (indent left, right, etc).
The icons are weak. Save (a ring?), Cancel, Delete all have the same colors. Those are buttons with important differences and I feel it is not good to give up visually underlining their meaning by using colors for a UI that reduces color usage to 4 (white, green, gray and light gray). This may look posh, but it doesn't help me in developing things fast and relyably.
So, for the current state, I am not convinced this is a step forward.
