No disrespect to you but you are a light user. As a heavy user 16 GB of space is very light. I have run into the same issue. I had a 920 w/ 32 GB internal and upgraded to the 1520. I've been forced to uninstall several games to keep free memory space.
GoVoice is the main GoogleVoice app. Additionally there is a beta app out called Groovester which works with Google Music. I have had a Samsung Focus for a year and a half and love it. Next Ph phone is a Lumia or Titan Two. Thanks for your posts.