Can I get advice for my conflagration build?

First of all, This is my conflagration sorcerer build.
And I have trouble in choosing which skill to be assigned to meteor shower.
Currently I am using OFF but after I saw OFF doing nothing to bosses and enemies immune to freeze(not even a tick for proc? seriously?),
I decided to replace it with something better.

I have 3 candidates on my mind. Canister bomb, Flashbang and Mortar trap.
Canister bomb has guaranteed proc chance with large AoE stun but CD is too long.
Flashbang has great CC and big DPS boost but low proc chance often makes me throw it several times which is pretty annoying.
Mortar trap is basically the easiest to use (fire and forget) thus very appealing since I love firing my burning laser continuously but otherwise it’s inferior to others.
Which one should I pick? Any help would be appreciated.

Oh and one more thing. Should I replace Chariot of the dead+chaos crossroad to Oklaine’s lantern+jackal?
I find Wayward soul underpowered but offense ability is nice.