Well consider me sold on a sump then. Do I have to drill a 3rd whole for a second drain? (Heard this method greatly reduces noise) or will I be ok with the 1" out and 3/4" input I have already drilled?
Yes, a second drain will reduce noise since the main drain will always be under water and silent. Drilling is possible only if the pane you're drilling isn't tempered. If you drill tempered glass, well, this happens