Hey bro. I feel your pain.
I was GS till last Libra, and everyone says they farm more with less gear. It isn't possible,they wright absolut nonsense. If any GS will same gear/level I beg for you to make a video,open your inventory/skills show everything and go do ToI and post here the outcome.
I came to believe that due to most farmers,Yul class they nerfed them by adding bow resists to mobs making Yul life difficult.
Lvl 114 with gr skill+20weapon,+8r110 set,agathions +7,cloak+7,Skills +10/+15,artifacts +4 ... And I couldn't aoe iOS 110 or ToI 1.
Changed to DN and I can do both instances now and I'm missing greater rune skill, some ++ skills ,weapon aug...
Please don't bring DK into this, you can't compare DK with any other class.My DK has same gear and he farms more in iOS , he can farm more then 2 DN in TOI/atelia, all same gear +/-.
It was hard for me to change,believe it. But if you want to progress and be able to do all game contente,either change to tyr/dk or get in to a good cp.
Best of luck