I'm not very happy with the current situation myself. However, i don't like the idea of adding too much stuff from AE back to jPCT either. Anyway, please give this jar a try:
http://www.jpct.net/download/beta/jpct.jar. It adds the keepPixelData()-method (which isn't completely pointless in desktop jPCT if you set Config.glAvoidTextureCopies to true, so that's just fine) as well as the RGBColor-class (which simply extends awt's color class). Regarding Light, i'm not going to change that one. Afterall, it's just a different import.
Another thing that you might come across are methods with "filler objects" that i've introduced in AE. I.e. instead of writing
sv=Object3D.getTranslation() you can now write
sv=Object3D.getTranslation(toFill), which will fill the "toFill"-SimpleVector and return it in addition. Android's garbage collection is so bad, that it's mandatory to avoid creation of short lived objects at almost all costs. However, this somehow clutters the desktop API, because it's simply not needed there. I've tried to back port these methods anyway.
I agree that it would be best if AE is a strict subset of jPCT, but i don't think that i can ensure this all the time. If you stumble upon other stuff that's missing, please let me know. Maybe it's not intentionally and i just forgot to back port it.