The reason I ship Dramione is because it was the first thing I ever read on this site! I was just kind of browsing through everything and decided to check out Mischief_managed18's Dramione piece (go check her out, she's amazing!!) and I loved it so it's my main OTP.
The subjects I'd probably enjoy the most would be Transfiguration and Potions, probably because I like having to refine skills and having that challenge to get it perfect every time. I would probably enjoy Divination and Astronomy the least because both deal with uncertainty and they just seem very flimsy to me.
My favorite canon ship? Oh boy immmmm.....the one I use the most is Harry/Ginny, but I think my favorite is probably James/Lily because I've actually started to learn how to write them! They've always felt like challenges to me and now that I'm starting to write with them I'm loving them more and more!
I would have to say I'm a cross between Hermione and Luna. I'm very organized about all of my homework and try to do it all in a timely manner, so that's the Hermione in me; but, I'm also in a lot of fandoms and on Tumblr and so there's the Luna in me, because I can be really weird sometimes.
Thanks for the questions!!