Hi BE.
The stern davits are purely optional. (No holes cut into the stern, so leaving them off isn't a problem). It is important to note that if I were to design the stern as per her Trafalgar configuration, the stern would look very different to how it looks today, on the real thing. If I did design the stern as per 1803/05, too many people who don't know what it actually looked like would complain and say it's wrong.
Also, I don't buy the built up bulwarks for the forecastle. I have only ever seen these on Victory on paintings of her taken years after Trafalgar, where the artist has incorporated configurations contemporary to the artist, and not of 1803/05 (one famous painting even shows Victory with a later round bow with continuous front bulwarks). With a 'square' forecastle, build up bulwarks does not look right, perhaps looking a little awkward - But that's just my own personal opinion based on many drawings and paintings I have studied over the years.
More drawings/paintings than not show stern davits and timberheads at the forecastle, so this is what I include - but as I said, the stern davits are entirely optional.