If you can find some that match the gray walls or even find something not nightstands (wall mount shelf a with drawer comes to mind) that would most likely be best since you don’t want black nightstands.

How about mirrored small chests for night stands?

I'd go for either wood or something like a mirrored finish, depending on what style you're going for...

Those upholstered headboards always make me think of having to vacuum them regularly, especially lighter colors. But to each their own.

A lighter wood would be great like natural or grayed oak. Good luck!

I would go with light/gray

What about a champagne color?