Yeah, hallways are mostly for passing through, so I wouldn't decorate much unless you have beloved art that's looking for a place to go.

I find that hallways like that are a good place to hang family photos since family are the only ones who really use that space.

I agree about family photos.

I would add a brightly patterned rug runner.

I have family photos in mine. The one side has a large gallery arrangement with all color photos in black frames. The other side has b&w photos in black frames on shelves resting against the wall. I enjoy seeing all these photos as I pass through daily.

If you do go with photos I'd choose larger sizes. I wouldn't put a 4x6 on the wall without using a larger frame with a mat.

In addition what has been mentioned:

Colorful runner

Some really cool light fixture

Different paint for end wall

I can't tell, but is there space for a small table?

A really nice ceiling fixture can do wonders and you'll see a big difference right off. You could paint the doors black (or not) and upgrade hardware to brass, add B&W family pictures in a more modern concept per below on end wall and B&W wallpaper and you'll have a destination vs a passageway - lol.

I think hallways should remain simple. I like the idea of a runner and a few pictures at the end of the hall.

LOve that wallpaper Maureen!

I wanted to add a small table to our hallway which is similar to the one pictured above. Determined the only size that would work would be one of 8" depth and about 3 1/2' wide. Ultimate decision was that a table would impede traffic flow in the hallway. Therefore, what we did was across from the bathroom door added a tall floor standing mirror (just standing on it's own) for a full view before going off to work. Added a colorful runner. Looks good. If I had a picture, would post it.

You hallway is pretty broken up with doorways so if I did anything I would get the new light as mentioned or maybe even 2. You could try a runner but you might have trouble opening that door on the right. Plus the hall rug is cut off at the left corner so you'll have to figure out where to stop the runner and still have it centered in the hallway. Something eye-catching like the photos posted on that back wall would be nice.

Hanging cord relief - You can put something like this together yourself, and I found instructions for it before I saw this kit. I like how they trimmed out the plywood in one of those small pictures underneath.

http://www.homedepot.com/p/Attic-Ease-Pull-System-Kit-in-Pewter-AEPSP/204354248

Your hallway has a jillion door openings. Leave it as it is. It looks just fine.

Pictures and/or a runner. That seems about all that you would be able to fit.

Maureen- where can I find that beautiful light fixture in your last photo? Thanks!

I think you need two ceiling lights to lighten up the hall, and I love the example Maureen posted with photos on the end wall.