Took a look at his site. Some of the night stuff looks lit pretty good. Maybe some kind of dispersed light that's not too concentrated would help. But I'm sure its mostly just technique and practicing more.
Interesting, never thought to try light painting at a lower ISO and blend. This is a single frame of 25 sec, and yea I tend to blow them out as well. All this took was a few swipes back and forth after I blew out a few previous tries.