Tried out a very simple overlapping hexes pattern that I was not sure how to colour in. My first thought was various greys, but I went with something more colourful:
Bit weird. Looks a little like algal cells maybe. The central parts are yellow ink with green acrylic on top, but with gel gloss added to the acrylic. However, painting the acrylic layer on the varnish did not work out too too well. Or too well. Oh well.
Then the rest was a bit bare, so I filled the space in with blue and red inks. Not a great colour scheme. Top marks all round.