Sounds like you know pretty well what you want and how to get there. :)
What is the attraction of Materials Engineering for you? I admit I have never really explored all the options under the "engineering" umbrella, so I've never heard of it.
For me, its a matter of starting small. Noobs usually don't start out with Wizards or Blizzard, it will be a slow progression from small, independent companies and shows to "real" recognition. I've interviewed a number of "big" artists who all say that's what you have to do... so that's what I'll be doing.
As far as usefulness of classes, it really depends on the class and you. So far I have only had one or two classes that have been little more than practice (and an exercise in bullshitting), but most of them have greatly expanded my way of thinking and approaching art, as well as my technical skill. How much you get out of an art class depends on how you approach it. I know a lot of people who go in thinking they already know how to paint, and find the classes to be a waste of time, and wonder why they don't improve or get good grades. It also helps to have a knowledgeable professor who can give guidance and suggestions from their experience, whether or not you actually use their ideas.
Also some of the more specialized methods of art-making require some form of instruction... such as intaglio; which is a printmaking method using acid to bite an image onto a metal plate. There are now countless techniques for etching, so it would only make sense to have several classes on it or an apprenticeship of some form at the very least. Anyone can teach themselves to draw by observation even without instructive books, but no one can teach themselves intaglio from scratch!
Sounds like you're pretty busy too! I'm an Illustration/Fine Arts double major. The studio class workload can be pretty excessive at times, but this semester I've got a good balance between studio and academic classes. I hope to become a professional Illustrator after graduation. Really beyond that title, anything is open; magazines, books, newspaper op-ed, cd covers, etc. What I'd really like to do is concept art in the gaming industry and cd covers for metal bands. The key to this will be a rock solid portfolio and a few publications rather than resume building; its a Catch-22. You have to be in print before they will print you. :P
Free swag is always good... do you have any specific prospects for internship? I'll probably aim to get one not this upcoming summer, but the summer after that. I have a lot of work to do...
I'm taking a full 18 credit hours: Anatomy and Figure Drawing, Techniques 1: Color and Composition, Intaglio II, World Civilizations I, Ancient and Medieval Art, and Illustration Survey (the history of Illustration). The workflow is very constant, but do-able. I've also gotten quite sidetracked with a few personal projects; teaching myself how to block print, a comic book, and so on. I'm also trying to make time to do mundane things such as grocery shop and go to the laundromat, which I have to do for myself now that I'm in an apartment, as well as paid work at the computer lab 19 hours a week (where I am now). How about you?
Yeah! No problem though, take your time, I've got a lot of work piling up for my classes, but the debate is a nice refreshing thing for me. Its so different from everything else I'm doing and confronting.