Ah, I see you are also a man of culture.
You may be interested in this guide I wrote and
just updated that is focused on making the Hansa the best they can be. Always looking for feedback and improvement!
BTW, the +15 hansa (surrounding with 6 +2 districts) was
possible before it was just incredibly annoying. Nowadays, you can pound those suckers out in a group of 3 cities if you want (see my guide for details.)
~~~~~
As for the thread topic
I find Aussie to be quite strong, but you
have to fight the AI to leverage their +100% prod ability; humans can easily circumvent it. Ignoring that totally OP ability though, just the combo of coastal housing, adj from appeal, and the outback station are crazy. They're like the inca in that regard. Absolute tile yield monsters.
But for the reasons the OP stated, I do feel like Germany is one of the best peaceful (or at least, not rush strat) civs just because they are so darn reliable. You can roll out the big

anywhere any time, whereas eg inca needs some decent mountain hills to really shine. The extra district (for rapid building and easy time locking in costs) and the free red card make for such a well rounded kit. I
know that short of being on a five tile isthmus, i can succeed as Germany in any start.
But otherwise I agree with Archon. Sumer/Nubia/Aztec/Maori are just too good at consistently obliterating people in early war and having strong economies to leverage the gains. With the Toa nerf and the legion getting half iron usage, and the new importance of aqueducts, and the ability to rush t1 govt, Honorable mention for Rome in my book.