Assassin Poet's Pen Barrage Fire Conversion with Flame Wall

Hello guys! I 've played a Barrage build in a CoC setup with Poet's Pen and Flame Wall before and liked it and I thought I could maybe try something similar, with the difference that Barrage will be my main damaging skill. Made a pob that looks quite promising, Sirus dps is 1.7 million with Enemy Low-Life ticked and by the looks of it, its defenses seem ok, though I could use a second opinion regarding this matter.

The build has about 7500 EHP, but no other defenses other than block, Rumi's and Endurance Charge generation which is questionable. I'm using Rote Reinforcement for Endurance Charges, but I'm thinking that maybe it should be swapped for Enduring Composure for more consistent generation, though the armour component of it will mostly be wasted, but maybe it could still be worth it. It also seems to be not very expensive, except for some specific gear pieces. It also has shock immunity and some further ailment mitigation through Pantheon powers.

I'm kinda hyped with it and I'm thinking that maybe I could go with it as my second build for the league. What do you guys think?

Here's my pob link: https://pastebin.com/X5pXzDhe