Work them around the render. Create a flow of light that enters from one point, and exits at another. It's not that the light streams shouldn't be add, it's that you seem to just throw the light streams on-top of the render regardless of flow.

Here's some **** I did quite some time ago:
http://img204.imageshack.us/img204/9...domsiggy08.jpg
http://img687.imageshack.us/img687/4...domsiggy10.jpg
http://img52.imageshack.us/img52/333/randomsiggy09.jpg
http://img109.imageshack.us/img109/6632/blank05.jpg
http://img340.imageshack.us/img340/9...domsiggy01.jpg

Some of it is pretty bad due to excessive black-blank areas, but overall I keep the flow of light, and direction in most of them. The last one is probably the best example of flow since everything comes in from the left, and drifts towards the right.

Edit:
Better, but still old, examples:
http://img440.imageshack.us/img440/4...anavatar2w.jpg
http://img822.imageshack.us/img822/558/dadoavatar4.jpg
http://img843.imageshack.us/img843/2...eryavatar2.png

wow
 

amazing work!!! I like them all :O

Just gonna bump this here really quick, showing my work from then to now.

http://i.imgur.com/mwENM.png

http://i.imgur.com/ZH9mY.png

http://i.imgur.com/zdqHO.png

http://i.imgur.com/zDW2I.png

And another:

http://i.imgur.com/Bkgit.png

This was really bad, unplanned, and kind of a clusterf***. The color scheme was HORRIBLE at the end, so I was done with it and added a gradient map.

But here:

http://i.imgur.com/nXong.png