If I want to listen to music, I just go on youtube and watch music videos, so I probably won't have that many songs downloaded on it. I will be mainly browsing the net and downloading apps. Also, I don't have a netflix subscription, so will not be using the netflix app and downloading tv shows/movies. As for downloading stuff online (other than apps), I won't download that much stuff. Maybe every once in a while I'll download something.
Read more: Would a 16 GB iPad be enough for me?