Help with Tectonic Slam DW

Hi
At first sorry for my English (It's not my native language).
Second thing,Im playing for fun.

Thanks to Tectonic Slam 60% of phys damage is converted to fire. I know that I can convert remaining 40% to fire thanks to Magmatic Strikes but its not change to much in DPS and i cant leech, thats why i want to stay as a hybrid.

I'm Dual Wielding swords and i don't want to change it.

My setup looks like this
Tectonic Slam-MPDS-AFDS-Fortify-Pulverise-Multistrike

I use for buffs:
-Herals of Purity + Culling Strike
-Herald of Ash
-Blood and Sand

I chose Leap Slam as a travel skill
And Endurance Cry for regen and charges

Here is my Passive Skill Tree
https://www.pathofexile.com/fullscreen-passive-skill-tree/AAAABAQCAAHcAecC9gUtBTwJuwuNDjwOQxDwFCAUTRRxFewYkRkuG6ob-iKvJd8oKjGeNZI26DhTOYY6UjxbPQBAoEYOR35IeEnVTeNQR1cNV1RYr1oyXhNgQWFSYxdjcGVNbNhul287cq92rHbnd-N4DXrvgTqBm4IHhNmFUoZgirOLT5Ool3mZK5r-my2bap7Nn8ukGaZXqW6tjbXyuR28n702vYG-eL6nwBrBB8VTxqrKkM1fz37SIdVl137Yvdlh2XzcMuRR7w7vTvCi8kHyWvKc82_3vvjv_Ev-Cv6P?accountName=DarkPrince8&characterName=DarkPrinceM

Ok so I realy want to play as a Gladiator using Tectonic Slam and I have couple questions:
1. Is it even possible? I don't have problem with clearing up T16 maps, but Boss fights are terrible. I need about 3 min to kill map Boss. The same thing is with Conqueros.I defeated all 4 of them but Sirus is a different story. I dont have enough time to hit him more than 3 times becouse he is always changening his position and my hits are to weak.
2. My DPS right now is about 112.500 with only 5% crit chance.
I took all crit chance and crit multiplayer nodes near my character and i had only 13,5 chance to crit
My question is : Is it possible to play comfortable without scaling crit chance?
3. What can i do to improve my single target DPS? Thats the only problem that i've got right now

Survivability i think is on quite good level:
4,800 HP + great life leech
18,382 armour + Fortify and Endurance charges
77% fire res
76% cold res
75% lightning res
15% chaos res

Can somebody help me boost my Single target?I will be very thankful.
One more time sorry for my English