I have a double kitchen sink now and am replacing it with a large single sink. The current sink has a disposal in one basin and a standard drain in the other. The disposal is connected to a trap and then drains through the floor. The other basin is connected to a trap and then drains through the back wall of the cabinet.

Is there a preferred drain to use? Either one looks like it could be plummed without issue. The other one will be trimmed and have a cap cemented in place.

For background: The sink is under a window and the space below it is finished. I believe that the installation is original to the 1981 house. All of the drains in the house are PVC and there isn't a vent in the roof over this (or any other) exterior wall, the closest vent is above the bathroom approx 15' from the sink.

Thanks,
Tad