Civ VII Shawnee Playthrough Thinking

So one of the runs I'm looking at doing early when Civ VII releases (maybe not first, since India and maybe Maya into *something* are also calling my name at the moment) is a Tecumseh/Shawnee diplo run. I always enjoy trying to be suzerain of tons of city-states, so Tecumseh's bonus seems really fun, and the Shawnee seem to tie into that fairly well too, so I can pick any Antiquity Civ I want and then use Tecumseh to evolve into the Shawnee.

I'm curious though, what do you see as the ideal precursor Civ for playing something like that? Greece is really diplo-focused and has similar bonuses for being suzerain, plus the Xenia tradition (Increased Influence towards initiating and progressing the Befriend Independent Action).

Except, Tecumseh doesn't have a river starting bias, and neither does Greece, and the Shawnee's primary ability is "Settlements built adjacent to Navigable Rivers gain increased Food on River tiles, but Cities not built adjacent to a Navigable River receive less Food." So obviously I can found settlements by navigable rivers I find, or just tough it out and ignore that downside, but that still seems like a waste and/or assuming I can be picky with city locations when I'll have starting biases for a bunch of other terrains in Antiquity, and am probably sprinting to the Distant Lands when I become the Shawnee.

So, Mississippi and especially Egypt are river-focused, with Mississippi having a rivers starting bias, and Egypt having specifically a navigable rivers bias, and a ton of perks for playing alongside rivers, but neither really play into the diplo bonuses/suzerain playstyle I described above.

TLDR: Since the Shawnee don't have a proper predecessor (since the Mississippi people have a unique culture and very different playstyle), what do people think is the best Civ to start with if you play as Tecumseh aiming for the Shawnee?