Usability notices:
1) Two main "Confirm" button could use some post-click animation. Perhaps some "Click" sound would get annoying soon, but animation (however basic it might be, like the OnHover highlight effect for "History scroll") would enhance the experience a lot - thing is, reaction to your action is not instant, and every time you click and wait you get an psychological uneasiness "Have I hit the button accurately?..".
Same for "Replace activity for the day" buttons.
2) There's no easy way to see what is your Max Vitality - you only get the reduced amount in red, and clicking on it brings the explanation, but not the numbers. Not good. We need all the information.
3) Stylish "Thingie" in the upper-right corner is, no doubt, stylish, but it grows old pretty soon - and then it's just a mess. I understand it might by too late in development process to actually replace it, and coding in an alternative would take too much effort - maybe different sections could at the very least be colour- or icon-coded, so that it would be possible to insta-click whatever you need nowr
4) Activity effects should be included on the "Pick activity for the day" window.
5) There should be big convenient "Go back" button on most screens. E. g. "Expand choice on screen" pop-up. Better yet, [Right mouse click] should "cancel and return" wherever possible.
6) Text is too small on large resolutions. Can we have at least resolution switching, if not font size alteration?
7) Also - why the game is so unresponsive? One second wait on simply switch to inventory on Phenom X3 looks... weird. I guess there is no hope for post-release optimizations? History of a day loads for a fdew seconds. No big disaster, but it surely doesn't add to the feel.
All in all, the game is a ninth wonder of the world. Seriously: you guys rock, every penny spent was worth it. Thank you! But the interface honestly can win "Clunker of the year" award any day. Hope things will improve to the best...