Sorry. My fault for any confusion.
Just to clarify, personally, I would expect to have to pay for certain plugins and themes - as I’ve always done with WP - but I threw the concept of a premium version of CP into the mix because maybe it’s something that does need to be considered even if it’s just to rule it out. I don’t agree it automatically means a bullet in the head.
Regarding GPL, you wouldn’t actually be paying for the software per se. You’d be paying for enhanced support. Given that CP is intended to be a business solution, I don’t think having a community edition and a supported professional edition is a completely unreasonable (or novel) idea.
Maybe not today or tomorrow though…