I would think a sunny yellow or minty green, like cocos Melon one would work really well. I would steer clear of cream/browns , work find for a boy , but as soon as there born, you wish you'd waited till birth to see what you were having as it suddenly looks so generic! If you go for a pale unisex colour , with some walls white and also accesories white, then white unlike cream, goes with any accent colour. So after birth, you can easily add pink or blue etc touches in the room and it will team upl nicely with the crisp white, but no painting needed
We have Duck egg in our bedroom, so Devon has that too, I'm dying to paint his end of room jungle theme tho with huge giffafes and jungle leaves on the wall......