A glossy finish will serve to hide many imperfections in your concrete including repairs, cracks, patches, pour-backs from trenches that may have been applied separately from the original concrete. A glossy finish also blends any stain work much better giving it a more smoothly flowing appearance. A glossy finish is more modern in appearance and makes the floor stand out more. A drawback is that it is easier for scratches to stand out and you should be more careful not to gouge the floor with anything.
A more antiqued look would be achieved with a matte finish. A matte clear coat will also provide a bit more traction given the orange peel effect that the clear coat gives. The matte finish will make all stain, repair, and patchwork stand out far more. A small drop from our sprayer will be more visible from further away and it'll make any transitions between colors stand out far more. A matte clear coat will be more forgiving if you scratch it in terms of not standing out as easy.