Killing dragon now gives a buff to your team: + 180-270 gold on your next kill / assist
instead of an instant 180-270 gold.
The buff would last for 4 minutes and would promote aggression during that time.
The idea is to make it so that winning teams who have destroyed all the inner and outer towers don't feel compelled to just choke out the enemy team for 15 minutes and take dragon two or three times while slowly building up an unstoppable gold advantage. With this change, the winning team is forced to push their advantage even if it means risk and opening themselves up to being outplayed.
Waiting game is not fun. Risky team fights and dives at the inhibitor turret that could really go either way is fun.