Various points:
Yeah, martial arts will (or at least should) be a heavy commitment; better to put it off a while until you're more settled into your crazy schedule, speaking of which 14 hours work/studying and 4 leisure means 6 sleep which is Not Cool.
Ah, I've experimented and found out that 6 hours sleep works pretty well for me, now that I've gotten out of needing 9-10 a night.
Other than my absolute hate for polar graphing and anything involving sigma notation, not bad.
I actually used to be an engineering student. Engineers are ludicrously afraid of sigma notation, to the point of not being able to use it at all =/ I remember the final exam for my first engineering course gave an explicit formula we were supposed to compute, and most people had a lot of trouble with it.
Ehh.
You're talking to someone who can understand almost any concept intuitively and can memorize almost anything he writes down.
I've never studied for a test, and I generally calculated how many assignments I can skip while maintaining my GPA. If the answer is "All the homework" or the average assignment takes less time than my attention span (About 15 minutes, spread between 3 hours of other things) I move on to "What projects can I skip" if there are any.
My definition of "Too much effort" is where most people define "Too little effort."
... Wow, we're polar opposites. 4.23 GPA in high school and 14 AP tests (12 5's and 2 4's, for anyone who's counting). I study for each and every test, feel terrible if I don't finish an assignment, and can often concentrate my attention on one problem for 10-12 hours. On the other hand, I should have been called in for truancy given the amount of school I skipped.
Similarly to you, however, I also have an obscenely good memory that tends to drive other people crazy (since I can remember events that happened years ago as though they were yesterday). I just study really hard to back up my memory and intuition.