I'm using the default typeface (Segoe UI), with a 10pt font size.
Musicbee's pretty customizable, and you can make major changes by selecting and moving around elements in the Panels Configuration window (click the panels icon next to the search bar, and choose "Arrange Panels"). Here's a screenshot of the setup that I'm using:
I'm also using the "Album Covers" view for my files, which you can select in the header bar under the "Albums" option. If you want the fancy-looking progress bar, right-click your current progress bar, and select Panel Layout > Wave Bar. I've got my album artist photos cropped to a circle, which you can do by going into Preferences (Ctrl+O) > Layout (1) > Artist pictures: crop to a circle.
That should cover most of it! Let me know if you have any other questions or if you find some weird looking unskinned element.