Why????
My Lancer 29 also has a vinyl headliner..its an off white color..maybe even a light tan.In any event,I found a similiar color fabric to use when replacing the old stuff.The fiberglass under the liner is fairly smooth so I'm not worried about it pokeing holes inthe new liner but it was all covered (from the Factory) with some light foam...which is all still in decent shape so in most places I left it.In a few other places (where I find my head sometimes making contact)I added slightly thicker foam.Also,in the V-berth and on the side walls I went with some Radient Barrier material from the local hardware store..this is that tin covered bubble wrap stuff they make for use on windshield covers.Made a big difference in how cool the boat was last of summer.My point here is that if your worried about the rough surface making holes in the new liner go in with something thin,like 1/4" foam..or for climate control help,some kind of insulation.As for a Dark Blue vinyl inside a small boat..I think its your boat and you should decorate as you see fit BUT I THNK you'll find the dark color makes it look smaller and feel more like a cave than a lighter shade would.Good Luck & Fair Winds>>>David