Ironically, so far, Owlcat has had a great record with DLC companions. The twins in Kingmaker were actually tastefully done.
I went Monk/Student of Stone. It was pretty nice. But, I like monks, so take that with a grain of salt.
This combination has crossed my mind, and I did go through character creation a bit to mentally map things out, and it is a viable build - in theory. I'm not sure if there are any items to support it, though.
Mechanically, Aeon's number of bane charges stacks with Inquisitor's. But I feel it's actually a bad fit lore wise since Inquisitors are instruments of their god while Aeon's deal is not about any god in particular. So my Aeon PC ended up as a Quarterstaff Master.
Inquisitor works
I mean, I know Regill is awesome. And we all can agree he is. But his alignment is Lawful Evil.
daeran is secretly neutral good trust me
You can equip weapons mid combat, but I believe it takes a move or standard action so you'll be half a turn behind. No clue why Finnean isn't dealing damage, must be bugged. My general strat vs Deskari is to have one aoe blaster to kill the swarms he spawns, to split all my characters so that swarms and aoe will only hit one at a time, and to focus him down with my melee martials. Ranged characters are pretty pathetic vs him because of his concealment (that as far as I can tell has 0 counters.) Then you'll probably want someone to deal with nausea, some mythic paths are straight immune, but generally you'll need someone to spam remove sickness/heal.
Yeah Deskari is very hard to tank, try to use greater invis, he has a habit of dispelling true sight off of himself but you can dispel it too. Just make sure to dispel greater invis on yourself after the fight if you have enduring spells BECAUSE you need to talk to an npc after the fight and the npc doesn't have true sight or see invis.
Summoner works fine thanks to gaze that buffs summons and stacks with summoning mythic feat. Summoner inquisitor will give all of your summons teamwork feats. Abyssal sorc will give you max summons possible thanks to his unique bloodline passive. On last level you can dip loremaster and get druid secret and select purple worm, it will have godlike stats thanks to the buffs. Can go crossblooded sorc and grab lizard bloodline for free swarm spell.
I would go attack gaze instead of summoner's. I think high level summons have something like 20 base AB so I feel that even with all buffs they would still be mostly meat shields even with nobility, community and gaze. Attack gaze gives them more AB than summoner's gaze. This build is also frustrating since aeon seemingly only gets 3 choice of gaze early and that's only DC, CL and DR. The second gaze choice is M5 and you have to wait even longer for bane to summons and double gaze for both attack and summoner's gaze.
Loremaster spell secrets aren't in the game. Iniquisitor is nice for bane stacking but not super great summoners since you can't use a single spell more than once. And the extended duration is moot, your summons are gonna die quite fast regardless, it's better to just be able to swarm the enemy with a lot of them (Also inquisitors do not get access to high level summoning spells through their spellbooks). I would honestly just go druid or herald caller cleric like Delt mentions. Both can summon spontaneously and get to be full casters at that, and benefit from the aeon DC gaze which you will have to pick anyways. Plus Druid gets access to the crazy spider swarm summon, Elemental swarms and the worm.
Big words coming from a dude with that profile picture.
Iirc the summoner inquisitor subclass (monster herald? something like that) gets full summon progression as a class feature.
