Thanks so much for the comments, advice and complements

Yes, I do plan to put the decal on top of the Aqua Coat. The decal is kind of sticky on the bottom, so hopefully I won't have too much trouble getting it lined up (as best as possible) and then make small adjustments.

I'm glad you mentioned the ability to apply Aqua Coat over the top coat if needed. I'll be using water based varnish (Saman). Using water based products is all new to me, but aside from a bit of struggle to get the stain to my liking, I'm pretty happy with it.

I plan to put on a total of 5 coats of Aqua Coat so that I have a good thickness before sanding it. It's touchy; I wasn't careful enough and accidentally sanded through the first two layers of a small spot and removed a noticeable bit of stain, but I was able to touch it up to where it looked good again, thankfully. I found that sanding takes a very light touch at this stage.