When using collections, it's recommended to have at least 10% free drive space. This is for an retrieval reasons as well as exports of archives as DVS will be extracted to that partition as ARCHDVS files (though will only say temporarily).
Also, for adminstrative reasons I don't think I would dedicate 500 GB's for a single partition. That is why you can partition your storage. This will especially ease the burden of backing up your storage as a closed partition is a lot simpler to backup as the contents don't change as frequently thus backups occur less often.
You probably won't find any documentatition as there is no limit to the sizing of any partition. My experiences are that some administrators may feel it necessary to create a new partition semi-anually while other's may opt for once per year. But again, it is solely for administrative purposes so the responsiblity will solely be up to your EV administrator.