The way I do deck planking is to get a bunch of 1mm x 2mm tangynika, get the king plank in along the centreline then lay strips working outwards. At 1/96 that scales out to about an eight inch plank; maybe a little wide but it looks okay. I glue down with cyano. I don't bother to depict the caulking. A little surplus glue coming up between planks looks fairly convincing for that. The eye can see that this is not a single piece of timber with lines ruled on it, but many small pieces each with their own grain. The effect is very nice indeed. There have to be margin planks along the edges of the hull and in theory the individual planks should be rabetted into them but in practice at 1/96 it is not very noticeable. Once an area of deck is complete, rub it down smooth then give it one coat of a fine linseed oil varnish to seal it. (Le Tonkinois recommended) It is a lot easier to do than it sounds and goes pretty quickly.
Displacement would be about 18lbs.