Ability to set (throttle) data transfer (bandwidth) speed per user/package.
The idea here is to be able to allow User 1 (or Package 1) to have 100mb/second data transfer speed, and User 2 (or Package 2) to have 10mb/second data transfer speed.
So this way, we can use cloudlinux to limit individual users or packages based on data transfer speed.
(Sort of like how we can limit them based on disk IO, but instead... limit them based on data transfer/bandwidth IO.)
Pawel Panek commented
The bandwidth limit could be possible with virtualized networking. Please see this top-idea here http://cloudlinux.uservoice.com/forums/269295-general/suggestions/7196059-monitoring-network-activity?tracking_code=bebba4f4427672052edec4e8f4494643
Also check on this forum thread: http://cloudlinux.com/solutions/forum/forum18/topic563/
Consider moving your votes there as virtual network would provide the feature you're looking for and much more.
Yes, cloudlinux is awesome, but this is a basic that could have been implanted already. Sad, it isn't there yet.
That idea might be extended with limitting bw depending to file extension.
For instance: limit .swf files for 10mb/s etc.