I think the problem I have with the MC is that, even though it's fine to have him be patient, intelligent and generally knowledgeable, after some time he comes across as too perfect. He always knows exactly what to say at the exact right time and never makes any missteps, at times he sounds more like a highly trained therapist than a nobody who's been travelling for an unknown amount of time (which makes the prospect of romance with Asterion a tad awkward too, am I his lover or his therapist?). For example, take the scene where Asterion is trying to convince the MC to stop giving him hope for a better future and start treating him more like the prisoner he is. It's a very difficult situation to be in, if it were me I'd probably lose my cool and snap at him. But the MC manages to handle the situation in the best way conceivably possible.
Rather than customizing his character entirely, I'd like more options for him to not necessarily say the right things at the right time, let him be a little more imperfect, tread on peoples toes occasionally. I deceived Asterion into wearing the loincloth, it wasn't the right thing to do. Make more options like this, even going down the romantic route.