For ripping CDs, I use Asunder. Make sure you change the preferences for file format so that it saves the albums correctly by artist instead of the default artist – title.
For editing IPV3 audio tags, I use Easy Tag. If you add a image on the picture tab for each song, you also get the cover art on devices that support it.
If you actually want to edit an audio file, Audacity is great.
If you need an easy to use and effective file converter, try Sound Converter. It supports MP3, Ogg, FLAC, and others.
All of those were still in the repos for 16.04 last time I checked, so the installation is easy.