You should check the cases in person. I just came back from the Apple Store and Apple Leather Case and Apple Folio Leather Case looked a lot different than I expected (aside from Saddle Brown and Black).
I was originally on the fence between Forest Green and Black, but Forest Green looked much darker than I expected, which probably will become darker as it ages.
Saddle Brown looked best to me, but I had to pick my second choice of Black as Saddle Brown is not offered with Leather Folio Case.
I just got the iphone XS in space grey, I bought the apple black leather case with it but I'm having second thoughts, what other colours would you suggest that go? I was thinking of red but thought it might be too bright.