As someone who went to great lengths to upgrade an entry level Cannondale road bike, I fully support upgrading anything with whatever you want. Ironically, the only remaining original component, aside from the handlebars, is the steel fork.
A bonus to upgrading whatever you have instead of just buying a different bike is learning and improving your wrenching skills. Careful though, this can lead to wanting a second bike, maybe a third. Or perhaps a dozen.
So far, it seems you've had a good attitude in spite of some other members who have been...less than helpful with their comments. Definitely let us know how the swap goes.