I'm working on this with a friend and its not easy. What we've got would require a tech-savvy person to run the scripts, and making them has been a pain in the ass. Also, a fast computer is needed. I'm a novice and my friend is more advanced, but I have a feeling hers are more elegant than what we've come up with. And then of course, creating the graphics to be used is a whole other can of worms.
Green screen - is it easy to do? Yes. Is it easy to do well? No. I have 5 photography lights set up in a permanent studio, with the green screen being lit separately, and I'm still not satisfied with the results. Back when I started chroma a few years ago I had two umbrella lights and you could tell; it looked pretty bad. Also take into account finding the backgrounds takes time, even more if you make them yourself. What I would give for an extra room to make miniature models in and give my eyes a break from the computer screen XD.