Heh- he might not be typical, but my male ball python is the most active of my snakes. When I have him out, he never stops moving, wants to explore everything (my boas will normally poke around a bit and then just hang out a few minutes later).... and the ball is always roving his cage at night pushing on ALL the cage furniture. Not "timid" at all! But from what I've heard, that's not quite normal.....
From what I've seen of burms and retics, I'm not sure if they are MORE active than the snakes you mentioned... mostly I see them (at reptile stores in the area - they don't sell them here anymore but a couple of places have full grown retics & burms as "mascots") just hanging out just like most other snakes....