Mhalir is so scared.
He's keeping it pretty under control, it's not getting in the way of his ability to think, but the fear is still there. Mostly he's terrified of losing the war with the Andalites, who from the very beginning have thought Yeerks were inherently disgusting and evil just because of their physical nature, which they can't exactly change. All of them except Seerow (a sliver of pain, grief, he trusted Seerow, he misses him, and it feels like so much more than a brilliant scientist was lost, when he caught them by surprise with an attack and then died in the ensuing firefight.)
He's scared of Golarion. Mostly of its gods. Powerful entities with bizarre goals that sentient beings can't quite understand is terrifying to him. The supposedly-Good gods aren't much less scary, because he doesn't trust that their definition of 'Good', or come to think of it their definition of Law and Chaos, match his own sense of those concepts at all.
But Asmodeus in particular sounds pretty awful! Maybe not so awful that Mhalir, personally, wouldn't choose an afterlife in Hell over ceasing to exist, because ceasing to exist is the most terrifying thought he's capable of having and his entire mind runs from it screaming - (some other thought he manages not to complete) - but he can still imagine most Yeerks wouldn't choose Hell over true death, and so he thinks they can't afford an alliance with Asmodeus even though it could plausibly help them win the war, because he's bigger and stronger and smarter and even if they can trust him to keep agreements, Mhalir suspects a god could probably just outsmart him.
He does think that they're currently outside Asmodeus' reach, on a ship far away from the planet where they collected Carissa and the other weaker wizard, but he's not sure and that's also terrifying.
Focus.
He's still feeling admiration for Alloran's try at persuasion, and confusion - Alloran has spent most of the last fifteen years yelling vitriol in his head, shouting that he hopes all the Yeerks get dissolved in acid or whatever, and hearing him talk about how doing the right thing is important even when it's hard and probably won't work is...jarring, it's left him off-balance and dizzy.
He doesn't expect Alloran to have gotten through to Sevar, much, but the reasons why are also making him sad. He hasn't seen the inside of her head, of course. (He badly wants to, because he's confused about her and understanding her feels essential to this venture and all of this is so critically important.)
- he's sad because she seems to genuinely believe that Asmodeus is the most powerful being in her world, and also that Asmodeus doesn't want humans or other sentient beings to - have goals and ambitions and dreams? Apparently their religious philosophy considers the entire concept to be a flaw in human nature, which is honestly the opposite of everything Mhalir believes.
What does he want.
Thinking about his own goals and values is unlikely to be persuasive to her either, because she seems to just not believe in caring about other people as a concept, but it feels important to be honest, if he's to have any hope of getting her actual cooperation. Which he does want. He can extract valuable work from her regardless, but that feels so tragic, pointless. A continuation of the strategy that the Andalites pushed them into, everywhere else, but right now he's out of the Andalites' reach, in a world they don't know exists, and - it would be stupid, to let the horrors of the war up to this point force him to approach the Golarion locals just as adversarially.
He'll do it, of course, if it's the only way.
What does a Mhalir want...
He wants the Yeerks to be free and prosperous, able to invent and discover and explore. And he wants the Andalites to have the same, ideally, and for all the other species that have experiences and feelings to have the chance for those experiences to be ones of flourishing. He wants that future desperately, and he's not sure it's possible, anymore - so many possibilities were closed forever when Seerow fired on his people - but he hasn't stopped trying. He isn't going to let the Andalites massacre his people, never ever ever, but obviously he doesn't want to enslave everyone in the universe. What kind of victory would that be.
He's kind of ticked off with Alloran for slandering his genuine efforts to engineer a better solution to the Taxxons' hunger. He thinks plenty of Taxxons would still want to keep their Yeerks, just because they know each other, now, and because having a friend right there in your head to help you be your best self is nice. There are some early case studies on Earth humans having that viewpoint too, though he's very frustrated with Visser One's handling of the situation, even the 'voluntary' hosts are voluntary by a pretty stretched definition, her constraints are understandable but still.
He's suddenly sad and tired and he's not even sure why.
He wishes they could just - trade their resources, technology for magic. Build routes between the stars. There's a flicker in his memory, a shining city, the image is vague and feels at this point like a hopeless unreachable dream but he's never going to stop wanting and trying and having goals.
He doesn't want to harm Sevar and certainly he has no intention of killing her. He'll put a Yeerk in her head, of course, if he can't get her cooperation, and she might consider that torture, like Alloran does, and he feels a pang of regret for that possibility but it won't stop him.
...He wishes, vaguely, that she could have met Seerow, maybe Seerow could have better explained why he was doing any of it.
...
Having his thoughts read is making Mhalir self-conscious and as a result his thoughts are kind of going everywhere.