Well, on the first point, let’s look at an analogy. We have an all male priesthood, yet still experience a priest shortage. It’s seems illogical to say that a male that sees just males doing an activity will want to do that activity, or that if males see girls doing an activity they will not want to do it. Heck, look at sports. Boy and girls play soccer and basketball, and there’s no shortage of basketball and soccer male players. Furthermore, why not just seperate the male and female altar servers if you feel this way? Then they can both do it, without having to serve with each other.
Your second point, about why faithful Catholics would want female altar servers, seems to ignore other points. For example, if there exists even the remote chance that going to a co-ed school would make a male like a particular girl and, therefore, steer him away from the priesthood, than why would any faithful Catholic want co-ed schools. It seems ridiculous, especially because we do not have any specific proof that being an altar server has a direct effect on one becoming a priest.
I think that being an altar server strengthens someone’s desire to be a priest, and that it might even spark a small light that might bring a male into going to the seminary, but there are many other, stronger ways to do this (like various diocesan programs).