setup advice - time to upgrade?

as you are not a techie, and this is for business use, I will mention this:  A NAS is a great system for data storage, and the raid formating helps ensure the data is protected. HOWEVER a NAS is no replacement for having backups. It is critical, esp in a corporate environment to have backups as well--preferably offsite.

Look at using the old readynas but keeping it far from the main one.  I am not sure if the NV+  can use the replicate feature, but this would enable your new and this old readynas to replicate though the internet, meaning the old system can be put in another location.

Or look at a cloud based storage solution.  Or just a plain old external HD that you do weekly to backup your relatively small storage array.

Cheers!