[ALUG] Directories to exclude on a backup

I'm about to backup my system as I want to resize the sda1 partition and I didn't think it was possible to do that with an existing system. So I looked online and found a Ubuntu guide to it which suggests excluding the following directories :- /proc /lost+found /mnt /sys/ I intend to backup /home separately so I will also exclude that but is the list reasonable or are there others I should also exclude? TIA