Mitered squares here...
Honestly, I think we have enough colors of yarn to make each square a different color combination.
That bright yellow is causing me some concern. The picture doesn't show it, but it is not a delicate yellow, nor is it a cheery yellow. It's a very violent yellow, somewhere in the area of mustard and finding the right accompanying color to tone it down is taking some time. Navy blue helped it, and we're thinking brown or gray might work, too.
(This may be Penny's fault. She was with me when I bought that yellow yarn. I suppose she was too well-mannered to ask me, "Why on earth are you buying that screaming, obnoxious shade of yellow?" Clearly I was not asking myself the right questions.)