Beautiful image. As it's so large, I'd place a timber hall stand underneath it, and lean it against the wall rather than hang it, then I'd place a collection of relevant objects on the table.
1. A lamp, perhaps a ceramic base with native American colour and shape, or simple pottery base. With a simple calico shade.
A pottery or timber low tray with some tactile collectibles, like some river pebbles, different rock, a piece of and old timber branch, thats been smooth by touch, or timber carved balls. ( I know you're probably thinking what?)
And lastly, I'd hang it above the picture, or rest on a table a feather headpiece. You can get these online, even I've seen them around Melbourne in odds and ends stores.
Maybe if it's on your table, a timber head that milliners use for a display.
You could continue this look with an Aztec looking rug or cushions to break up your leather couch. Mohair throw might look good too.