Improve UI spacing on bigger text sizes

I think allowing users to set the text size instead of providing fractional scaling is a very good idea to begin with but the spacing between UI elements needs some improvement. For example, on Code (screenshot below) with 1x scaling factor and the font size set to 1.5 everything feels too compact and not really breathable and evenly spaced.


I think a good rule of thumb to get the spacing right would be using `xrandr` with the 2x scaling factor to zoom out the screen (screenshot below) so that the zoomed out font size on 2x matches the preferred font size on 1x.


As you can see, the scaled down version looks more pleasant spacing-wise, the titlebar is bigger, the tabs view is bigger, the drop-shadow is heavier and there is much more spacing between the menu entry and it's corresponding keyboard shortcut. The wingpanel is also more comfortably-spaced as opposed to the first version where the applications menu is so near my monitor bezel I can't stand it.