Like Don said, your black dial PAM 90 will take just about any color strap.
To many eyes, lighter color straps do tend to frame the watch somewhat better than darker straps... but...
I love my burgundy gator strap on my 90. It's a deep, rich color that appeals to me. We had a similar one on my wife's 48 but it got moved over recently in favor of her new red gator.
I don't think the gators are too blatant or obvious and I think they lend a richness to the look of the timepiece.
Just my opinion.
There are literally hundreds of great choices out there.
Have fun looking.
And, great choice of PAM.