Yes. A zero fret
used to be the sign of a cheap guitar. It was done as a production expediency but how does that preclude it's use in a hand made instrument? Cheap guitars now a days don't use zero frets. So, if you follow that sort of logic then cheap guitars do not have zero frets therefore if your guitar does not have a zero fret it is cheap.
I have never felt the need to give the bass strings more clearance whether with a nut or zero fret. It's an easy way to fix a buzz with an open string but that is as far as it goes. As soon as you fret or capo you lose the benefit. If I did raise the action at the nut then I might also need to shorten the distance to the first fret a little to compensate for the added stretch the string will require (nut compensation). When I first started doing zero's I used a tall fret, but after filing every one of them down to get the action right I gave up on that theory and just install a slightly wider one now. It's an aesthetic thing. Nothing functional at all.
An added benefit of a zero fret is that you can change string dimensions and not get nut buzz because the string was too loose or get a bound string because it is too tight.
I like both ways. If given a choice I'll take the zero fret though.
Greg N