I hadn't thought of tan at all.
That would be a great choice...and I could simply weave in a pink ribbon on the bottom if it's a girl. I also really like the suggestions of gray and deep red (a color I am currently using to make my 3 year old daughter a sweater). Those would be so easy to make! And, honestly, I can embroider, so if I need to, I can embellish the sweater later.
Actually, now I want to make several sets in just about all of the colors mentioned.
I will have to buy all cotton, as they live in Houston, TX and won't want terribly heavy clothes (the nice thing is, the baby is due in October...so by 3 months, s/he will need some little sweaters and hats!).
I need to get cracking...just 8 months to go!