The second photo (dark brown leather) looks great.

I personally like to contrast the dial. In this case, a dark strap allows the colorful dial to really pop.

Definitely don't color match with a tiffany blue strap, or it will be WAY too in your face.

The bracelet option would be my second choice

 

I'd pick up an Elite Silicone strap in white from Barton. The white strap would complement the white hands and indexes. Would be a fun, summer-vibe look. Orange might work, but it would have to be the right shade of orange and you run the risk of looking garish.

 

My wife said almost exactly the same thing

She really like a purple strap with it too, but I don’t know if I’m loud enough to try turquoise and purple!

 

All of them look good to me. The sand/tan one offers a nice contrast, and I really like it on the bracelet as well.

Good luck with your decision.