What pot for this dude?

Hi all. Advice wanted. I think I’m coming to the point this spring of needing to put this handsome boy into his first real pot. But I’m a bit stumped on style. It’s a black Cherry plum, so we have:

• Pink flowers on bare branches in very early spring
• Light red leaves in spring darkening to deep red in high summer as shown
• Gnarly black trunk
• Annoyingly deep relict stump in soil that will probably rule out a very shallow pot this cycle

Anyone feel inspired? I am thinking a rectangular pot to match the trunk, but ideally with some “softening” features (lip, decoration, etc) But the colour has be totally stumped.