Sort of a headache thought (shower thoughts, but with a HEADACHE) but I really think Genos will manage to break his limiter and go beyond the capabilities of his mechanical body.
He says he’s after total destructive power, but what he seems to seek more than anything is the ability to protect others - which is what he wanted during the fight against Elder Centipede. He wants the power not to destroy, but to protect, and his biggest limit right now is his body, so easily broken.
Which is 100% why I think the way he will remove his limiter- if he ever will manage to do so - will be through learning, or finding the ability, to repair himself and upgrade his body and weaponry. Eventually, of course, and definitely not soon. But he might.
And we already caught a glimpse of that, through the same fight I mentioned before. He got cut in half, but somehow he managed to put himself back together. No welding marks, no signs of his previous injury. I highly doubt it was a mistake on Murata’s part (let’s be honest, the guy is super meticulous with details) or the centipede’s acids.
I know this is too far fetched to be true, but it’s a thought / theory I like to entertain. He’s growing more human by staying with Saitama’s, and he’s forgoing being a merciless destructive machine for seeking the power to protect. I’d really like to see this kind of development for him.
