"I really wanted to test the beta version but I simply cannot work with this new layout."
Shame, but I feel the same.
I used the previous betas (10,11, versions... etc), but I started the 15 beta only a few times.
Ugly, and unduly large UI elements
Reducing the icon size does not help, because the smaller icons will not be more visible (disabled or not), and the smaller icons are blurry, even worse than the normal sized icons.