Credit can be given as "Wikipedian Kbh3rd" when any of my copyrighted images are reused. A link to my English Wikipeda userpage is appreciated but not required. An alternative form of acceptable attribution, when technically possible, is simply a link to the image description page, the image description page on Wikimedia Commons being preferred to the transcluded instance found on Wikipedia.
I wrote my own program to draw SVG maps directly from GIS data. Anyone is welcome to try it, if you're not scared by the biggest, hairiest command-line syntax you ever saw. It is written in Perl and runs on Linux. It might work on Windows if all the required packages will load into your Perl environment there; I've never tried it.
I keep a full gallery of original work on the English Wikipedia. Here are a few samples of the various types of images that I've contributed.