Weasel disk partition plan

Currently I have two partitions, root and big. They are both managed by lvm and look like this:

root@weasel:/boot# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/Ubuntu-root
                      224G  107G  106G  51% /
/dev/mapper/vg00-big  230G  187G   32G  86% /big

It would be much more reasonable to have a small root partition that is easily backed up and separate partitions for /home, /store, and /big.

/store is a shared network-accessible space. /big is used for automatic backups of root, /home, and /store.

/store is 99G, /home is 3.4G, root is 107G, so if I would split them apart, root could be as small as 5G.