Possibility do define SubDomain home folder

I would like to request a feature that is found in most Control Panel (cPanel, Ensim, Helm, Plesk).
 
When we first created a site, (with IIS) HC will created a similar structure in the IIS server  :
 

 :\websiteFolder\domainname.com\www
 :\websiteFolder\domainname.com\log
 :\websiteFolder\domainname.com\...
 

 
But when creating a subdomain, the option to point the home directory to a sub folder of the existing domain should be available. Currently, HC will created the subdomain as follow :

 :\websiteFolder\sub.domainname.com\www
 :\websiteFolder\sub.domainname.com\log
 :\websiteFolder\sub.domainname.com\...
 

 
But I would like to option to either created a sub domain like HC is alreayd doing or select a existing folder of the current domain EX :
For the main domain root :

:\websiteFolder\domainname.com\www

and the subdomain root :

:\websiteFolder\domainname.com\www\mysubfolder

 
Currently, to archive this I have to change the home folder manually in IIS, but most end user createin a website will request/need this feature while developing a website.
 
Thank You!

Such implementation was using by HC in older version but this was changed on number of change request from different customers, this is what I received answer..
But still it is a very valid request and should be considered.