[please ignore that one of those is aether and the other is chaos; I’m only trying to understand the principle now.]
You can’t afford to ignore this, I’m afraid.
In essence, this is a game which rewards players for specialization. How the big picture works is as such:
(Flat damage * %bonus damage) * (100% - Enemy resist) = Final damage
^Note: If you reduce a targets resist to -X%, you essentially amplify your damage by X%.
This is why resist reduction is so sought after in this game.
But I digress.
There are tonnes of minor details I could include to paint a more accurate picture (e.g. attack speed, attack animation, etc.), but let’s ignore that for now as it’ll serve only to complicate my explanation.
As of now, I’m guessing that you’ve taken spectral binding which gives you flat aether damage + %aether damage.
The aether scythe you have in the screenshot is probably taking that into consideration. In essence, the larger the flat damage pool, the more efficacious each percent in your %bonus damage becomes.
Looking at sheet values alone and ignoring damage type is a dangerous precedent.
Since you’re a ritualist, I recommend eventually transitioning to the vitality route seeing that both the necro/shaman masteries give huge support to vitality damage.
The reason for this is simple: The higher the difficulty the game, the more resist monsters pack, the more important resist reduction (RR) becomes.
x1x1x1x2 did a magnificent cabalist which I’m sure can be jury rigged for a ritualist with relative ease: http://www.grimdawn.com/forums/showthread.php?t=73102&highlight=vitality+bone+harvest
Mad_lee also has a fantastic ritualist I’ve test runned for him. It’s not unrealistically impossible to gear for either. Especially if you’re ok with trading.
I’m uncomfortable sharing the GT link as it’s his and he hasn’t posted it yet, but feel free to PM him for ideas/advice. He’s our friendly neighborhood Russkie. 
EDIT: If aether savagery is something you still insist on, look up veretragna’s lord of the watch. http://www.grimdawn.com/forums/showthread.php?t=74335&highlight=Lord+watch