I think meditation would be a good way of raising Psyche. Or, when the game asks you about one item that you’ve always kept and the religious texts. If I recall correctly, one of the options was definitely Buddhist teachings, which, as I recall is normally about discipline in some manner, could also raise psyche.
AS for some of my own suggestions, I would really love to suggest other ways to raise certain stats, i.e. strength, agility, etc. Through an actual gym. Although, I don’t imagine a regular gym would increase superhuman strength. So maybe being on a squad of other Enhanced humans route would grant a sort of stat of the art sorta gym. Heavier weights, faster treadmills, etc.
I think that studying in any sort of way should also minutely increase intelligence. But what if superhuman intelligence? I’m thinking a special headset, similar to the one you see Charles use in XMen. Increases his psychic powers dramatically (hey, another way to increase Psyche?) But there’s also the potential for a tonne of information at your fingertips.
In case you get called into the police station to join the superhero squad. I think I’d like to explore a bit more with them before the actual ending itself. I love the game, but I want more from it, so additional quests never hurt. I thought an interesting thing to explore with the said squad was the idea that was mentioned even earlier than that point. Maybe some other countries have formed their own squads of enhanced humans, it was said that other governments were looking for more stones, and looking into the prospects of making super soldiers. So an encounter with such honestly wouldn’t surprise me at all!
Lastly, the last thing I want to touch on, even though there’s plenty of ways to increase your martial arts in one way or another. Something a bit more illegal for the villains I thought would not hurt. Rather than the gym is an underground fight club (which we do not talk about) for you to partake in to practice your skills. Or even the possibility for an enhanced human underground fight club somewhere that’d give opportunities to test out certain things.
As for the villains, once again, I do think it wouldn’t hurt just to purely go the hero hunter route for just hunting heroes, and potentially killing them off. There are a few times where your character screams they’re the most powerful, so I thought if that was really a motivation, that would be a fine way in proving it.
Obviously most of these aren’t necessarily small changes, but I just had some things I thought was worth mentioning, haha. Love the game, by the way.