Your comparison of why alastor likes vox vs husk, makes me think about what vox would be like if someone owned his soul
If a non-alastor owned him: he would get out of it eventually. Hes clever and he would not give up, much like alastor. It would probably take him longer, cause there are some things he is not willing to sacrifice (like he would not intentionally sink his reputation, he cares too much). But I believe in him
If alastor owned him: I think there would be a honeymoon period where he would not even try to escape, like dont free him he is exactly where he wants to be. But I think eventually, even if it takes decades, he would start to try. I dont think he would succeed, just cause alastor makes him lose braincells even if alastor himself wasn't so clever. But he would try.
So it’s funny, I agree with you on the first bit (if Vox ended up in contract with someone other than Alastor) but I actually think his idea of “trying” under contract with Alastor would be to keep amassing power but not get out. Which would actually be very entertaining to Alastor, and leave him outside of the Husk bubble.
Come on this journey with me.
Let’s say Vox did the unexpected and takes Alastor’s dare of a deal at the end of Ch. 4 of WFLT (where Alastor was like if you really have given up, prove it by selling your soul to me for protection). The actual outcome of this path would be these events in the following order:
1. Vox wallows in his misery for a little while. Even here, his misery stabilizes around the idea that even if he’s lost everything/everyone, Alastor still wants him for some reason. So yes he’s upset, yes he’s pathetic, but he’s also trying to pick himself enough to keep appealing to Alastor (something that is normal to want and possible to achieve) which eventually leads to—
2. Vox tries to get up!! This is very challenging from his present position. He is just a head, he is in enemy territory, he is at the questionable mercy of the Radio Demon. I think his first play would be trying to be useful to the hotel in some capacity because obviously they’re a complete disaster and he has intimate knowledge of what a disaster they are from all of the spying that he’s done.
3. Alastor finds the above efforts combined with Vox’s horrible, terrible mood swings to be satisfactory enough in combination to give him his body back. Vox with a body redoubles his efforts, which are also now more visible to the hotel crew than ever because he can walk around and do things manually.
4. Once the hotel is running like a well-oiled machine he starts trying to butt into Alastor’s radio broadcasting shenanigans, because Vox has detected yet another thing that isn’t Optimized for Maximum Optimization. Alastor damn near bites his head off (again) but eventually redirects him to other things.
5. Vox ends up once a-fucking-gain trying to build a media empire. He’s just not an Overlord while doing it this time. Which makes it purely a business arrangement, I guess? All Alastor knows is that whenever he looks away for fifteen seconds, Vox is doing a new ridiculous thing. It’s like bees and beehives. He’s very self-motivated.
6. They end up having some sort of a Niffty-Alastor type dynamic where the Vox is not even remotely trying to get away, but is wildly industrious for no apparent reason, and holds intense and unyielding affection for Alastor. And if someone aims a gun at them Alastor will feel compelled to put an end to that for some reason.