As your tango collection grows, the need to get more accurate and consistant meta information increases. To tag your music from an online database greatly reduces your effort.
To combine MusicBrainz Picard with genre and recording dates from tango.info, you can use these plugins for MusicBrainz Picard:
tango-info-plugins (zip file with both plugins)
put in the plugins directory of PicardQt together with http://open.tango.info/tracks.csv and enable the tango.info (date) and/or tango.info (genre) plugin under Options.
Note that due to a bug in Picard, both the release date from MusicBrainz and the date from tango.info will be set if both exist. The tango-info-date plugin also sets the tag recordingdate as a workaround.
Some TaggerScript may be useful to customize the formatting of artist etc, and other plugins that I have found useful are Disc Numbers and Cover Art Downloader from http://musicbrainz.org/doc/PicardQt/Plugins.