Yes, creating anything above 32x32 pixels exceeded by icons design skills (and I've tried ). Those icons now include versions up to 128x128 pixels, so you'd probably be able to spot the different countries in that version.
I was probably too brief in the changelog, but you now can add custom buttons to the toolbar using View → Customize toolbar... (or Customize... from the toolbar context menu). This includes buttons for any tag source/action with the option to customize the icons.
Apparently change is hard for me... At first I preferred the old icons so I switched back to them as soon as you could. That was too hasty. Now two months later, after some playing around with the new toolbar config, the new icons have won me over. They are a more clear and distinct design that I like which also make them a tad quicker to spot, at least for me - especially the "Convert" ones. So for me, the new icons are the clear winners. Thank you for the great amount of thought and work you obviously put into this.