Well, even if Patchou gives us the new plugin interface's documentation (if there's any), you won't have Plus! 3.10 to test (unless you are an official tester/translator), right?
Incidentally...
To be honest, every plugin developer has his/her own wishing list indeed; for example, I, with a view to improving of Hopper, want Patchou to include display name changer. If Patchou adds every plugin developer's request, the whole plugin interface may get instable, insecure..etc (well I don't really know if this'll happen though).
Why don't we have a nomination and then have a vote?