Hi Martin!
Auto-hiding our very right scroll-field - all right, great idea.
- it should be possible to show it again via (Window -> Show the cool thing) <-- or similar wording 
Yes, I'm for it

This hiding-thing may not be recognized/noticed by everybody. Say I accidentally close this menu... I think first thing I do is to go to WINDOW => PROPERTIES PANEL in order to switch it on again

Let's enable both ways so that if somebody won't find one way one of them - there will be always another solution for the problem.
My other "ideas" as far as UI is concerned:
- clicking on a guide should cause opening some toolbox where you can write precise guide position, agree with me?
- Shortcuts options for CHARACTER STYLES? (say CTRL + 1, 2, 3, etc...)
- Shortcuts options for basic text operations like increase/decrease font size, increase/decrease distance between lines/letters in selected words... This small things speed up creation/designing process/entire workflow a lot.
- I think I've mentioned that before - when it comes to ARRANGE PAGES... I can't make it any smaller in height (attachment) Hope this could get better with our new UI?

- Need to simply how pages/master-pages are created... Simple + / - icons for the pages and + / - icons for master-pages could do... (in order to create/delete them - I lack an option to CREATE NEW PAGE from this toolbox in v 1.5... Duplicate page option would be also a nice one...
Kind regards!