I agree with @wadestriebel this is still only 5 people giving input.
As it is, the plugin type or category is okay as is, from a user perspective, I want to know the plugin that is specifically developed for CP, and NO, I don’t want a plugin listed in the “Developed for CP” category just because the author or the dev says he is committed to supporting CP., they might decide not to support CP down the line if they don’t have the capacity anymore.
In fact, this happened to me recently, I was using a plugin where the dev claimed it supports v4.9 upward (CP works fine with the version 2 of the plugin), and he released version 3 which also claims to support v4.9. Out of curiosity, I asked the dev if he would be willing to support CP officially, he said that shouldn’t be a problem but he is gonna get back to me.
He got back to me saying v3 is not compatible with ClassicPress or WP v4.9 anymore because it depends on features that were introduced in version 5.0.0 which is quite extensive and would require a rewrite specifically for CP. Still stuck on version 2 of the plugin until I think of what to do.
How many of this would you test yourself when the plugin directory grows?
So, If it is developed for WP but working with CP, it should be immediately dumped in the “Works With CP”, this is still from a user perspective, I want to know what is what.
If you feel the need to improve the ecosystem or if you feel the need to welcome WP devs that are making a commitment to CP, you might create a new category specifically for them, but you don’t have to. Just don’t merge anything together, please don’t!!!
Please let’s not further complicate things