Two-tone seats...should I do it?

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I've been thinking about this for too long and need some outside views.

I think I like the idea, but can't land on a definitive decision. Should I two-tone the seats with white leather or leave them be?
If I do decide to go with two-tone, should I do just the rear insert, or the rear and the bottom cushion?

Below is a mock-up with some white cloth for a rough idea.