Hasta La Motion!

Hi. I started to work on my showreel, and I hope I can jump into industry with it. And Im wondering what shots I should focus on. Lot of you guys here are in industry, so I would like to ask you what vfx houses expect from a junior compositor or roto reel? What they want to see?

I believe that Im not going to impress anyone with explosions, or bullets stuff, so I was wondering about focusing on multiple layer and more complex composition, or they care more about easy composition and watch how clear it is? And what about roto? Does reel with for example surfer on water is valuable then running dog? Or it doesnt matter at all?

And last thing. I liked the walking paper giants in The Mill showreel for example, so If I lend this idea and put similar dudes in different city footage ofcourse, is this a problem? Will they look at it and say "bah its stolen from The Mill, thats bad" ?

Sorry for big amount of question, I dont expect answer on everything point by point tho. Just a little push in right direction, because Im really confused about this. And ye, I tried to search about this, and I found lot of great and helpfull posts, but nothing really specific. I know from this site that I should put in best shots, keep it short, etc.

Thanks ,)