I agree with you for the most part.
But, I do this daily. With Seal-it. I never have to wait longer than 10min for the polish to be dry (as long as you applied the polish in thin & even coats, and it's not old grubby polish).
And the IBD uv topcoat that I mentioned is designed SPECIFICALLY to go over polish. It's cured under uv light.
My clients went into a revolt the day I ran out of seal-it before my order came in. They love that their polish shows absolutely no wear & tear between appointments.
I tried using coloured gels in the beginning, but didn't find it cost effective. To spend 15-30$ on a colour that maybe no one would like? I'd much rather spend my 2-8$ on a polish and if no one likes it, it hurts less to throw it out.