Problem Bridge Arbeistbereiche

Which beta are you using (the number please). 

You seem to be talking about two things: one the Workspaces and the other accessing the desired folder. I'll attempt to help on both.

I completely agree with you that accessing recently used folders in the new Bridge (both 13 & 14) are extremely frustrating. However, If you can take a Content Panel you do not want and wish it to be a recent folder, you can (1) go to the "Clock" icon (to the left of the boomerang) and select a recent folder there. (2) You can select a folder from your computer and drag that to Bridge and it will open in the Content Panel that you wish to switch to the one you want. There are a few other approaches but that should get you started.

As far as Workspaces go, there have been a few issues with Workspaces but to my knowledge and experience, most of the issues are now gone. I think you are aware that you can create your own Workspaces, save them, and even update them. When they seem to have gone wrong and wish to restore them to their previous structure, you can go to the three lines to the right of the Workspace's name (in the US we call them the "hamburger" menu) and you'll see this:

Note that in the last item, you can reorder and even hide workspaces. 

Please let us know if this helps resolve some or all of your problems.