Expanding into non-CS fields I believe is a great idea, as CS is a science, lots of great cross-polination of knowledge could be amazingly helpful one day. Pick something you find interesting and go for it. Even if it is not science related, many fields are in need of good programmers to move them along to the next level, and the more you know, the more valuable you may be.

However, you mention that you aren't getting the high 'A's anymore. If all your classes are so trivial, why not? I assume you've spoken to your professors, or the dean of CS? If not, i'd do so. They may be willing to bring you into some more challenging environments if you show an interest and the capabilities.

I dropped out of Uni, and have absolutely no regrets. But you sound like you would be really into it if it were more challenging, so maybe stick with it.

Is there a local tech company that you find is doing interesting work? If so, before dropping out, you might be able to work a program where they bring you on as a co-op with the University. That way you get the challenge along with true work experience, the business gets a deal, and gets to see how you work, and the university gets... I have no idea what the universities get, but in Canada, co-ops are pretty common, I assume they are in the US too.