Why not just just use an inexpensive netbook PC? You can download all the stuff you need, open it in several great programs that you can get for free. You can purchase a refurbished netbook, which is not any larger than some of the tablets I've seen lately, for as little as $50. I've been using a 9-inch Acer Aspire netbook PC for a decade, never had a single problem with it, and the view is HD from nearly any angle.
Good luck on whatever you decide upon.
PSR-S950, TC Helicon Harmony-M, Digitech VR, Samson Q7, Sennheiser E855, Custom Console, and lots of other silly stuff!
K+E=W (Knowledge Plus Experience = Wisdom.)