Nice work so far.

If that were mine, I'd put a coat of clear over everything, then distress the crap out of it. Follow that up with a black glaze (basically paint you apply then wipe off selectively), then another coat of clear. The black catches in the distressing marks and makes them look old. Doing it to the legs and the top would tie it all together and make it look unified.

Fill that pocket hole with stainable putty, enlarge randomly, stain appropriately and it will look exactly like a knot.