Oh, they are a bit sloppy about interior changes now, methinks. The wooden Cessna 206 panel is still available on avsim ...
Well, to be serious now. The reason why Carenado does not provide a layered paint kit is simple and straight-forward: They don't give avay their secrets. The way M. Illanes blends photographs with photoreal-style painting is an outstanding craftsmanship and i'm sure he wants that technique secure to himself. And hell, no one can (or should) blame him for that.
But even with a bare white bitmap a skilled repainter can do miracles. There's no need for rivet lines and things like that, they are all present. All you have to do is keep on trying. A old copy of Photoshop or PaintShop will do the job perfectly, even paint.net can do this.
Now the mirrored textures are indeed a little nuisance here. They prevent larger reg numbers and additional lettering on the fuselage and wings. Surely a layback on a repainters imagination for unusual liveries, but i can live with that. A poster further above said it correctly: Most G/A planes are indeed white with some stripes, and the average simmer doesn't care at all.
Additional texture files would blow up the overall texture load for FSX, and don't forget the fact that still most FSX simmers do not have a state-of-the-art rig to max out the sim.
All right, that all sounds a bit like a scoolmasters speech, but beleive me, i have some knowledge about repainting Carenado stuff. They provide the best textures on FS aircraft ever, and the best "paint kits" to work with.
just my 2 cents ...
cheers,