I found that using Lite Tweaks does a great job at cleaning things up.
I have also been "carefully" using Bleachbit, which offered a lot of translation files to remove.
On one PC that I use infrequently, but do keep up-to-date it had 900MB+ of extra files...!!
Having done some Googling it appears that apt-get pulls lots of translation/language files.
I also found away to limit the extra files, so far it appears to have reduced the extra files.
You may want to test this on Virtualbox, or a test box.
gksu leafpad /etc/apt/apt.conf.d/00aptitude
Then add this line to the file, there is a blank line at the end of the file
Acquire::Languages "none";
So it looks like:
Aptitude::Get-Root-Command "sudo:/usr/bin/sudo";
Acquire::Languages "none";
The apt-get update part went from @ 18~20 secs to 7~8secs
and Bleachbit finds no extra Language/Translation files to remove.
I should note, I have English only in my Language settings