Hmmm... what color should it be...?

Okay... so I've been busy cleaning and scrubbing and disinfecting stuff, and now it's time to make a decision on what color these walls should be... I'm not sure where to start. I love a nice, bright, airy room, but I don't want it to be so light that it has no character and uniqueness to it. I love blues and have seen medium to darker blue walls (and they look beautiful), but my space is really big and I don't want to make it look smaller unnecessarily... hmmm. Solution! Went down to Lowe's and bought some paint samples (these things are great!!! Only $2-3 per container, and you can paint a swatch on your wall to see what you think... Love this!!) to see how different colors would look. Whaddaya think?