8 GB / ........LVM
5 GB /usr .....LVM
5 GB /var .....LVM
5 GB /tmp .....Ext2
5 GB /opt .....Ext3
4 GB swap .....swap
You know that LVM is not a type of filesystem, right?
If you actually plan to use the same type of filesystem for /, /usr and /var,
then why putting /usr and /var on separate partitions? I can only see
drawbacks. Those I mentioned earlier.
And, currently the partition for / is huge (given that its largest
subdirectories are in separate partitions), the one for /usr is tiny (most of
the application files are in /usr) and /opt probably is too large (in
Trisquel, /opt is used to put application you install by hand; otherwise it
remains empty).
Is there any advantage in using ext3 instead of ext4? If you cannot answer
this question, you should choose ext4.