Thumbnail sketches are used to get down a concept quickly, in a small space before taking the time to sketch it out on a larger scale with more detail. You wouldn't want to spend hours on a concept your lead isn't going to approve, so you make several thumbnails of it, for environments I usually do 4 to a page. But yes, a thumbnail is a rough rendering of your concept. As for the PoV, that depends on your direction. Eventually you're going to have to model it in 3-dimensions, so the more views you can bang out for it, the more complete the concept will be, and the better off it will be if it's going out of your hands and to a modeler. But in terms of presenting to a lead, you'd probably want the view the player would see, and a top-down view of the area, laid out almost like an isometric map, with points of interest marked out. Does that help at all?
I don't know anything about VFS, but I do know there are a lot of game deisgn studios in the Vancouver area. Take a look at this:
From what I've read, the best thing you can do for yourself if you have no experience is to go to go get a Bachelor's. It doesn't necessarily matter what you get it in, or where. What matters most is that you've completed it. Especially for degrees that require you to work on a team for some capstone project, those are definitely a great thing to show that you can work in the industry. But if you can do it, you might as well take a specialized game design degree, just make sure you know what you're getting into.
1. Is the university accredited? Obviously VFS is, but how many classes have graduated from the program you want to attend? what's the placement rate?
2. What kind of degree is it? A lot of schools have a degree for "Game Design", but that's not what you're actually doing - you're learning a general game programming degree, and maybe some courses of a more general nature. If you're deadset against programming, try and find a Game Art and Design degree.
3. What kind of courses are you going to be taking? You want to make sure you're getting some diverse classes in there. Being a game designer takes creativity but it also takes a lot of knowledge of the world around you. So if you can choose your electives, choose humanities courses you're interested in, or art history, or psychology, sociology, ethics, etc. ALL of these things, and so much more will help you become a better designer.
4. Game design, and.... A lot of smaller companies can't really justify hiring just a game designer whose sole purpose on the project, from start to finish, is just to design. So they hire someone who's good at one thing like programming or modeling, and who also is a good designer. As the industry matures, I think you're going to see more and more places hiring game designers specifically, and even sub-divisions in that design team such as junior designers. But that doesn't mean you shouldn't learn something else. Explore the whole industry, and see if anything else interests you. The more skills you learn, the more valuable you're making yourself to potential employers. And along with making use of random knowledge, a game designer really needs to be at least briefed in the languages of his or her teammates, because you'll need to communicate with artists, programmers, marketing, etc to get your ideas into production.