You know what I've discovered in making icons? Shows like BSG are super-pretty to watch but don't always icon well. The framing doesn't give you a lot of options. Older shows like B5 and TNG tend to leave a lot of headroom, and it gives you a lot more freedom in cropping.

Of course, it's a double-edged sword. You have to do a lot more work on coloring and contrast, especially on B5, which I swear to God was filmed through cheesecloth.