I prefer the partially submerged shark ones. It's nice to leave a bit to the imagination. I would chose the first one.

I would definitely stick with the partially submerged ones, my favourite of those is the first.

I couldn't discern that it was a laser mounted on the shark's head though, not until I read your description. Perhaps include some kind of strap around its head to make it clearer that it's attached to his head? If that doesn't look too silly at least.

I am going to disagree with everyone here and say I like #3 and #5 the best. The outline and the body coloring make the shark look way cooler, and the submerged sharks just look weird with their faces invisible imho.

Also, if you do want a submerged shark, I would move the water line to the fin - generally just the fin is sticking out, not the whole of the shark's dorsal part, unless it's a beached shark - and make the rest of the shark a lighter shade under the line, as if you were looking at it through water.

It would be sick with the shark bigger and the JLAB the shape of the shark.

I can play with it tomorrow when I'm at work and show you what I mean. Similar to this hammerhead logo

Hint: convert the text to paths and move the individual points.