I was also thinking about the urborg/yavimaya possibilities, or lack thereof. Green and black are also the colors best suited to tutoring lands, so a theoretical azorius domain commander would have a hard time finding the right lands anyway.
By my math we're still missing a gruul uncommon legend, so most likely I think we'll see a RG domain option too.
I guess you could make it work with the triad of
Urborg, Tomb of Yawgmoth,
Unstable Frontier, and
Thran Portal, except for the GB one, and there are a reasonable number of green land tutors. Definitely playing on hard mode, though, compared to playing/fetching a triome and a dual and having 5 types on turn 2 with minimal effort.