Hi all, I have around me model boats and yachts that go back as far as 1960s and a restored one that must be 80 years old.
Not a sign of glass fibre on any of them. If you build in wood then a few coats of thinned varnish will toughen the surface, then just get rid of your old paints as you brush the paint on and wet and dry in between. With different colour paint layers you can see how deep you go when using wet and dry to get a good surface.
Most of my models have 10 plus coats of paint, well keyed in and have lasted well. I usually finish with an abrasive rub down of Vim (seems to have vanished from the shops) and then a couple of coats of good quality polish.
If you need strength in a hull start with thicker planking, just how strong does a hull need to be? I agree you can obtain a pristine finish but few full size boats are like that.
I also note that some go off into the realms of marquetary with deck planking. Most full size decks used teak for some very good reasons.
Over the years I may have refurbished a boat but one of my oldest has balsa planking and has survived very well.
By the way inside I sometimes use old stocking panels and varnish, just as good, also a good substitute for canvas. Many working boats from the 50s and 60s had canvass decks as well.