Spiffing up an old skin-coat boat

I have an old S-Glass/Kevlar wildwater decked C-1 that has been sitting outdoors for years now. The deck (medium blue)is way faded, and the hull (white) has taken on a dingy yellowish hue.

I really want to spiff it up as best I can and start paddling it again. Normally, with a gel-coated boat, some wet-sanding with 400 or 600 grit paper and an orbital sander would work wonders. However, this is a skin-coat boat, that is, NO gelcoat, just pigmented resin. I am afraid that even light sanding with 600 grit will put me right into the fabric. I am even concerned that hand buffing with polishing compound might have the same result. In the past, I have gotten away with wetsanding skin-coat Wenonah’s and bringing out the color and shine again. But the skincoat on this boat seems paper-thin.

Are there any products out there, either marine or automotive, that would feed, nourish, and restore the color without being abrasive, or at least only very mildly abrasive?