Is there any guidance available on how best to provision disk space for BIG-IQ VE?

I've just managed to secure some more storage for our BIG-IQ instance, however I need to know which folders need the most space to be allocated to allow importing of config from our BIG-IP devices and managing backups etc.

Current storage is allocated as follows:

• Size Used Avail Use% Mounted on
• 287M 206M 67M 76% /
• 1008M 40M 918M 5% /config
• 3G 1.8G 306M 86% /usr
• 9G 654M 8.8G 7% /var
• 7G 7.2G 2.0G 79% /shared

I've got an extra 250gb to allocate - I can see /usr and /shared both have a decent amount used already, but I'm not clear where the backups/config files etc are stored once we start using the system in anger