So I keep wanting a black dialled diver again.
"Want" you notice not "need".
My SMP has a blue wave dial so that's a different box ticked.
Today I've taken delivery of a Longines Legend Diver which is in a super compressor style case. I think it will stay at least for a while.

I think I'm trying to justify a Planet Ocean. There, I've confessed.

I've added a picture of my black or blackish divers watches and it surprised me to be staring at five watches. The PD Eterna is a long-time keeper, the Eterna Kontiki 7750 grey dial is a grail watch for me and I wear it weekly. The O&W 7750 I've only recently built using case, dial & handset with a new Elabore-grade movement so that one is staying.
The oddball on the left end of the photo is at least a diver and it's a WUS Forum Limited edition built by Vostok so is of relatively low value but could go to make room.

Can you see a space for a black PO?

 

I would exchange the Porsche Design for a PO. This way you won‘t have to occupy extra room. Just my personal opinion.