I have 720 songs (incl'g 2 audio books totaling about 40 hrs), 2 movies, 5 half hr TV shows, a dozen music vids, <100 pics, 30 apps, 28 ebooks - have 21.5GB free out of 29.3GB available on the 32GB model.
On my 64GB iPad - have the same 720 songs, 1 movie, 16 half hr TV shows, the same dozen music vids, 258 pics, 55 apps, 35 ebooks, 15 comics, 31 magazines - have used 12.7GB on it.
The point is, if pricing is a concern, it's easy enough to manage carrying what you need with the 16GB devices.