Hi Paul
I have attempted water once using lots of coats of clear varnish tinted with some grey, brown or green depending on what you are looking for. I painted about six layers in total. The small waves were made with some clear gel-type glue and apinted on with a brush and licked up like a curl. A few layers of varnish untinted on top to finish. A bit of white drybrushing on the tips of the waves before the last varnish coat helps. See below for results! This works well when there is samll area of water.
Your dio is excellent and a good idea to try out out something differnt from a tank and broken wall. Maybe some of your figues could do with a bit weathering/ drybrushing to bring out detail. But all the ground work looks excellent.