I'm fine with this story's approach to characters. I have read SO MANY manga and manhwa and manhua with ultra strong protagonists. I rather lilke that this MC is so different.
As far as I understand this is going to be a really long one, so I'm fine with the slow development as well. And it would be completely unrealistic, at this point in the story, to have romance I think. It does not really fit with the MC personality, nor with the girls personalities. They're all very "immature", it's ironic that the blond M guy is the one who is thinking the most about romance.
I assume that all the girls have... issues, different ones for each of them. So I find the idea of a slow burn story enticing.