>>11797306pretty realistic, although a lot of details are simplified or ignored to make it possible for one autist working alone to implement, like hydrogen/fluorine rockets being fucking amazing because you can just pour them into some UHMWPE tanks and not worry about it
a lot of the material properties are kinda sketchy too, both because there's a lot more details to them than you can easily implement and in a lot of cases there's only really shitty information available