I think that Europe is fine as it is. Dark green is too close to blue/teal what is tier 1/2.
Personally, I think the new green is easier to see than the bright green in use on the main site now. It's contrast with blue is fine, and while it is closer to teal, I can still easily tell them apart.
Since the new green is on tmtest even for Europe, feel free to check it out. Italy and Russia struck me as particularly good regions to check (Russia especially as the Europe select freeways don't seem to be much more common than the American ones, so it's hard to find instances where they go near each other elsewhere).