Poor performance for my ilvl

[Eimi]

Hello! I recently swapped to mage after not raiding in Tomb of Sargeras, and for the first couple weeks of Antorus I was playing catch up, and expecting my damage to improve. However, this week with 4 pc tier gear I am still lagging substantially behind the other mage in my raid, and am performing terrible for my ilvl. I know that Soul of the Archmagi isn't very good, but compared to my other legendary's it's the best option at least according to raid bot. (Vashj's, Norgannons, KJBW, Ice Time, Zann'esu)

Here is the parse of our normal clear and the first two bosses on heroic for this week, and the only fight I even did what I can begin to call okay on was Argus. https://www.warcraftlogs.com/reports/6AHC2mKvZDVPaWTp (I am Aleksandara)

Is there anything obvious I'm doing wrong or just fundamentally misunderstanding? Is it a stat allocation issue with my gear? Currently my secondaries work out to 35 crit/20 haste/59 mastery/14 vers. Which I know isn't perfect but I am following the suggestions from RaidBot.

[Unreal]

Typing from phone, so I'm just taking a look at the obvious things.

Talents: Glacial Spike vs Thermal Void. You're playing a vastly different build. You should look into thermal void builds.

Gear: your itemlvl is quite inflated due to the fact that most frostmages at that ilvl are still using t20 2p in combination with the new 4p. Your teammate is still using t19 2p with t20 4p. He simply sims way higher than you with 941 ilvl. Quality of gear > ilvl.

If you have any spare tokenslots and a decent ring you could use lady vash glove legendaries. However if you do have the old t20, try combining the new 4p with the old 2p. Also switch to thermal void. You should lower your mastery and increase your haste for decent results with thermal void.