+1 here. Definitely would like to see day of the week type scheduling ability.
Also have the ability to specify a discovery window, for example 6pm - 6am. If the discovery is not complete by 6am, it would stop and post the discovered results and status where the discovery stopped (last address). As it works today, when the discovery timeout (6 hours) is exceeded it throws an error and all discovered nodes are lost. You have go back and tweak your discovery criteria and try again.
Plus, support for concurrent discoveries. Today, all discoveries are run on the primary engine. One option would be to add functionality to Network Discovery to schedule discoveries on additional polling engines. So, if Network Discovery could do at least 2 concurrent discoveries and you have 2 polling engines then 4 concurrent discoveries would be possible. That would be sweet! Single threaded discoveries just doesn't cut it for a large organization like us which supports several class B networks.