I actually have great expectations for the cross server event. As a player that is lvling and hovering around lvl 51 atm it will definitely be a fresh breath to fight against people who are roughly around the same lvl and power rather than getting 1 shot or hoping to fight a player who is also lvling up. Anyways I see it as a good thing for empty servers and for players who are in the process of levelling up.
I definitely see the concerns and would see a reward increase as a decent solution. When it comes to how broken it will be with matchmaking.. we will have to wait and see