Having found the geomorphs format for the contest recently, I’ve started playing around with a few more of those. Here’s a page of 6 I’ll be sending to Dave’s Mapper. (As such, these are CC licensed for non-commercial reuse with attribution [CC BY-NC 3.0])
Still trying out different styles and effects to see what works and what looks good. The top right one has its own multiple problems (not every experiment is a success), but I think they’ll all be workable.