I found the place to submit suggestions to dA for changes on their site. So here's hoping.
It's in suggestions. [link]
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
The suggested folders and sub-folders are shown below.

1. Scale Hobbies

------- A.Scale Models
\------------------A1. Architectural
 
\------------------A2. Automotive

\------------------A3. Aviation
       
\------------------A4. Die-cast
     
\------------------A5. Dioramas
     
\------------------A6. Figures
     
\------------------A7. Military
     
\------------------A8. Sci-Fi
   
\------------------A9. Ships
 
\------------------A10. Space
 
\------------------A11. Trains

\------------------A12. Other


------- B. Radio Controlled Models
\------------------B1. Air

\------------------B2. Land

\------------------B3. Sea

\------------------B4. Space/Rocketry

\------------------B5.Other

This list is by no means complete, or indicative of the overall hobby.

It is but one of many deviant classification changes dA needs to make, IMHO, to improve user friendliness and streamline the More Like This searches.