As it stands in the current state of the expansion balance is very weak.
I know some people are doing okay on the charts but the fact of the matter is we are at the bottom. Feral is doing insane single target DPS right now and we just can't keep up, not even on multi DoT fights.
I think a possible solution to our lack luster damage is to tweak the eclipse mechanic just slightly.
Our DoT's outside of an eclipse hit like a jar of piss, I think if the eclipse bar was changed to always be in either Lunar or Solar then we might just have the damage buff we need. This means removing the state of no eclipse completely and maybe tweaking how our mastery works just a little.
So say we have 100 solar energy once it gets to 0 it should suddenly tick over to 100 lunar and vise vera.
Alternatively a less dramatic change would be giving us a timed buff once we hit 0 letting us keep the effects of our last used eclipse state for 5 - 10 seconds.
I think this might be a better alternative than blizzard just giving us a straight damage increase to help us compete.