I'm working from an ipad2 16 gig. I have had this ipad since my 2 year in undergrad Micro. It took me a while to find a good document program for handling lecture slides. I finally settled for Kdans PDF handler since it lets me organize files in files in files. My entire college career is in this ipad, lecture slides, and several textbooks. I have never deleted any lecture slides or papers. I have had to convert Ppt file to PDF on a standard laptop and then mail them to myself since my doc manager only allows notes markups on PDF. I have yet to try the Word package for ipad.
Get the regular size ipad, and try a keyboard. I wish mine were a litter larger and I will buy the ipad mega when apple realizes whata flicking genius idea I just had there. In retrospect I would get a 32 or even 64. Not for games, just because of the amount of data I have ended up slinging around - med school bodes the possibility of even more data - and because doc handling apps flow a little cleaner on a 32.
Most doc programs I'm familiar with handle differently on a 32. I may upgrade when the loan refund comes in.