This is my passion! I say it all the time. I've come up with some great shots (by someone's standards lol)... but I've also come up with some pretty crappy shots too!
I've noticed that when there's no real plan and vision to a photoshoot, there's bound to be terrible execution.
I get messages all the time about shooting when I have free time, which is great! I love it! But sometimes it gets a little redundant when someone wants to shoot but they don't have a plan or theme.
It's totally ok to request to shoot but here's a little advice...
Come with a theme and/or plan for the photographer. To ask him/her to consider you for their next shoot is really shooting yourself in the foot. (No pun intended) lol Seriously though, you'll get a better outcome if you come with a plan!
Hope this helps! Let me know what you think or if you disagree!