Do you know the original reason you started using Distribution Servers (DS)? The benefit of not using a DS would be less moving parts, you don't have to worry about the DS being syncing with the latest data and patches before the deployment initiated. Also, a direct push from the Protect server not using a DS will copy out all of the patches immediately, using DS would delay the patches from being copied out there until the time of the deployment. So it could save time when using a direct push.
This information will help you determine whether you should be using a DS: http://help.shavlik.com/Protect/onlinehelp/92/ENU/EN/Why_Use_A_Distribution_Server_.htm