Daybreak is stupidly underpowered, you get 5 sword swipes which do pretty much squat agains bosses. I believe Daybreak needs a 25 - 45% damage buff and needs an increase in super duration
Dawnblade already has a really good duration. It also can swing 7-8 times (can't remember the exact number, but I know it's one of these 2). The problem with it in pve is that they do no damage. That was a problem with sunbreaker as well, but now we have access to things like roaring flames and they threw the embers onto it so the super is always extra lethal now.
Dawnblade might need more than just damage, maybe some stuff to help better with add clear.