Hey there Dr. Phantom,
First off, I'd like to say how nice it is to see someone sticking closely to the Dutch style. Yours is one of the nicest I've seen outside of the group of Masters. Have you considered entering it in the AGA Dutch category? I think it would be well received there.
If I may add a couple of minor critiques-
1. The lily is a bit too far forward and to the right, try moving it into the hollow next to the Bacopa that's currently taken up by Staurogyne. That'll put it in a good focal position and give you better shape and color contrast with the surrounding plants.
2. You're using a lot of similarly colored, fine leaved, species in the main section so the overall impression is lessened. Consider adding a darker leaved species with a bit larger foliage such as Anubias or Cryptocoryne to provide better contrast. Lobelia cardinalis would be another good choice and is one of the classic standards that'll lend the tank a more authentic impression.
3. I think I get what you're trying to do with the Staurogyne. It's making a nice street, but it's too similar in leaf shape and color to the Bacopa next to it to give good contrast.
4. The moss piece looks VERY nice and does a great job of adding some front-to-back interest and light vs. dark contrast. Consider moving the Bacopa to the left space where the Didiplis is currently. That'll give good contrast on the left side and will open up some space to bring the moss around the front in a curve partway along the Stauro border. Doing so will open up a space for a broad leaved species as previously mentioned.
Overall though, this is quite a pleasing tank and you're doing a great job working within the constraints of the Dutch style. *Thumbs up*
Regards,
Phil