Hello,
I have seen that people who hunt dragons decreased a lot since the event ended.
One idea I have to encourage hunting dragons is that players get a special item, like a Dragon Scale, for each dragon killed that could be exchanged for various items at the NPC.
For example,
10 Dragon Scales for a special potion
20 Dragon Scales for a Motif
30 Dragon Scales for a unique Furniture.
50 Dragon Scales for a furniture design
500 Dragon Scales for a special mount
1000 Dragon scales for a special house
Or something like that.