File Server Data Drive Partition Size Question

I am setting up Windows 2012R2 Server for use as a file server The drive space is setup as follows:

2 x 300GB  RAID1  for the system..

5 X 600GB RAID5 for the data .  Which gives me approximately 1. 9 TB of usable storage. 

I have approximately 70 users that will store documents limited to 3GB per user.

The remaining space will be used for shared drives between departments.

Initially I was thinking of splitting the space into two partitions.

Partition 1 Personal Folders  - 450 GB   (3GB Disk Quota enabled per user)

Partition 2  Shared Folders - 1.5 TB 



IS there a recommended way to Partition this space?  Is there recommended limit for the size of portions.  Would the above be optimal or should I look at creating smaller partitions?



Thanks,