ACR Freezes

Installers for older versions of ACR can be found here:
https://helpx.adobe.com/camera-raw/kb/camera-raw-plug-in-installer.html#12_x

You'll need to downgrade to the last version of Bridge using the CC app, click on the three dots and select "Other Versions".
That's about all we can do for you here. 

This is a user to user support forum so you're not being as effective addessing your interface concens.
You should go here to express opinions about the new build:
https://www.adobe.com/products/wishform.html

Select Photoshop for the feedback. 

In terms of the new interface, Adobe has stated:

"At this time, Adobe is not planning to revert the UI to the 12.2.1 state nor are there plans to offer both interfaces as an option in the future. That said, we are determined to fix bugs and improve workflows within the new user interface."

As for freezing, try trashing your Photoshop preferences. Press and hold Alt+Control+Shift (Windows) or Option+Command+Shift (Mac OS) immediately after launching Photoshop. You will be prompted to delete the current settings.

(Mac OS only) Open the Preferences folder in the Library folder, and drag the Adobe Photoshop CS Settings folder to the Trash. This action only affects the items found in the preferences dialog box. Numerous program settings are stored in the Adobe Photoshop Preferences file, including general display options, file-saving options, performance options, cursor options, transparency options, type options, and options for plug‑ins and scratch disks. Brushes (and lots of other setting) are not affected by the above instructions for deleting preferences. You may wish to make a screen capture of the settings in the Preferences dialog to reset them prior to deleting of this file.