Thanks, everyone!
I've got several things I can choose from now. I'm leaning toward "conscientious" but may use several of these.
or, depending on how you want to portray him:
neat and tidy?
Um... nope. Not quite what I'm going for, here...
"...such a Goody Two-Shoes"?
Now, now. In this story, she's reached the stage where she's very fond of him. While this
could be said lovingly, it's still not quite what I'm going for, here.
Terry - in this specific case, it's collateral damage; Superman's just catching the bad guys/helping clean up. But it could apply to the odd sign post as well. So far, he hasn't had to use any sign posts.
'Toc