When I was considering to buy the 5230G, my intention was to switch the original strap to a mate black one like the 5205G's (the dark dial version), with grey stitching to kind of dress the watch down a little bit.
Another option was to go for a dark grey strap matching the dial, which could look nice and be very versatile at the same time.
I experienced something similar with my 5726A, I wasn't comfortable wearing it on the black alligator strap unless I was wearing black shoes and belt. But with the grey composite, I'm wearing it much more often no matter the outfit.
And with the 5110G, which comes with mate black strap, I only have issues when I wear certain outfits with brown complements. But to be honest, the strap being narrower than today's standard width, it contributes to make it "less visible" and gives me some more "freedom" to combine it.
Anyways, I'm considering to order a dark blue strap, similar than the 5130G's one, which I believe is the most versatile option for the watch.