You could add some depth to the wall by staggering the pic arrangements.

add a couple of wall shelves for the pics to lean against the wall along with the other wall hanging pics.

You could even use up more wall space using this arrangement

You could put another row of photos, that should do it.

I think they are alright. You want your photos at eye level and adding more will either make them too high or too low. I like Bev's idea of a narrow console, but you would want something on it's top and then will interfere with photos unless you are careful.

Take the left set of three (vertical) pics and put two under the remaining two columns.

They're fine--you've done a great job. A console is a good idea--one without the bottom supports would allow you to add baskets or plants, etc to hide the electrical outlets. Very easy to do.