Given that I have at least basic understanding of typography, I would like to understand what attributes typography designers alter to make text more legible and more pleasing to the eyes?

For example, what features make `Consolas` more pleasing than old generation `MS console` font? Why does `Calibri` looks more spaciously placed than `Arial`? Why does `Segoe` look better on titles but uncomfortable in dense text?

I know anti-aliasing makes font appear smooth and serif fonts are difficult to read on-screen, but would request about other aspects of aesthetics of glyphs.