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Pretty much just comes down to personal preference at your point, go with whatever makes you happy lol. Assuming you have a standard size laptop, may as well go more for the portable smaller/lighter size imo.
I've recently got an iPad mini 2 and I love it. I personally feel like the mini is a better size for the kind of stuff you'll be doing (still large enough to watch netflix on comfortably but not too big for moving around easily). The mini 3 is out now but just the finger scanner thing is the only new feature and to me that doesn't justify spending about £80 extra.
If you want a fairly solid android tablet, you could get a Google nexus. There are adapters you can get which enable you to use the USB port to read SD cards.