Re: eye contingencies and Essek I think we did see him trying to check Caleb (see: the paper room when Caleb got distracted and tried to have them leave him on his own while they were trying to chase down lucien, but Essek and Yasha side eyed him and stayed)
Where Essek said he was uncomfortable with Caleb and Beau's eye markings, and asked him to give a warning if he felt the eyes were becoming dangerous, though Caleb just told Essek the others would kill him if anything happened.
Seems like Essek assigned himself to try and manage Caleb, between that and his constant checking on Caleb in battle
yes! i think it was a very interesting choice on matt's part to have essek only approach caleb about this, instead of one of the others (or even having essek follow up with other members of the nein after caleb gives his "my friends will manage it" speech). it gives the impression that despite his newfound love of teamwork, he has absolutely assigned himself this task alone. on a meta level, that's a little bit true -- the rest of the cast (minus matt, liam, and marisha) having a group chat on how to tackle this means that essek had no details about the nein's strategy to split up, and never got a chance to learn about it in-game due to the tight timeline. that invites a whole host of interesting questions: in the narrative, were the nein planning on having essek sit out the fight? (hard to say -- probably not, just from a firepower standpoint, but who knows.) would they have incorporated his plan to manage caleb? (very likely.) did they trust him enough to do that? (i think this would have been an interesting discussion, revisiting the trust of essek now that they'd spent more time with him post-vermus.) if essek had been the one to subdue caleb, how badly would that have impacted group dynamics, not to mention essek's own guilt? (oh boy.)
all said, you're absolutely right: essek probably would have been on caleb duty if things came down to it, self-assigned or otherwise. somewhere, in an alternate universe, aeor was a gut-wrenching wizard PVP, and i can only imagine what that would have been like