Is your child's room themed? Or is it just plain? At first we had it football themed, but now it is just plain. It doesn't make sense because he won't always have the same interests.
Babies enjoy whatever looks colourful and fun. So evenif choose no themes, the room should be with lots of colours and fun that make the baby cheerful and comfortable. Can make instant themes too using the available things (toys, posters).
I am planning to have theme based room for my baby pretty soon, and I have to work a lot to get my own designed and desired theme which would be little hard but achievable.
My baby room is plain but I make sure that there are a lot of colors to stimulate him. Decal stickers are a great way to add interest in a child's room without having to spend a fortune on paint and renovation.