I say the more events the better, especially alliance events.
As for rewards, i’ve heard alot of voices say gold rewards. Personally, i would love to see like a big amount of frags for hard to get heroes. Or the universal (don’t remember what you called em) frags.
Or even like 50 copies of an item that can’t be obtained yet through campaign or raids, which you need to get some heroes to high gold statuses.
Timewise, i think starting events in the evening is fine, like you do now. It’s usually 8,9 or 10pm for me and the other Dutchies.
It think it would be better to announce all events 24 hours in advance. Because the collect and create events start when almost everyone has done his raids and equipped gear to heroes during that day. This way, we miss out on alot of points, by not being able to wait until the event starts to do these actions