Few issues with V5 Beta 3

I installed V5 Beta3 today and the admin interface looks clean! I've been evaluating few enterprise level content management systems to deploy a site that will have hundreds of thousands of articles. They really don't need to be dynamic. So, Movable Type is getting close to my final pick for the project.

While evaluating the system I quickly found these issues:

To categorize the articles, I created 5 root folders (level I) with each of them having 1-3 sub folders (level II). I also created children of sub folders (level III). Below is the diagram of how the folders are created.
Destinations (level I)
->Asia ( level II)
-->China(level III)
--->Beijing(level III)
--->Hong Kong
-->India
-->Japan
->North America (level I)
-->USA(II)
--->San Francisco (level III)
->South America (level I)
Reservations (level I)
.
.
.
To organize hundreds of thousands of these unique articles (pages), I will need to create 3-4 thousands of folders. Here folders act as nested categories (taxonomy). So far so good, but what I found out is the Manage Folders page that lists all these folders does not have pagination support. Also, the folders are not sorted in a right ascending order. First a root level folders should be sorted and listed. So, in above case, the Reservations folder should be listed after Destinations, but it got listed as above instead. Instead of flat lists of folder names, indent or tree like structure would be a great usability improvement.

Also, I can't assign categories for an article while creating a post from the front end. The dropdown list contains the categories though.