Is ReadyCLOUD ready to use?

If you just want to access NAS shares via Browser, yes, you can just create an account, register your NAS to ReadyCloud with this account, everyone uses the same account to access NAS shares in Cloud portal. And I've checked again, you can use the same account in different PCs in the same time.
But you need to know, each ReadyNAS Remote account only can login one Remote client at one time, so you cannot use same Remote account login from different clients at the same time.
For large files or large number of files transferring, I think using ReadyNAS Remote clients(via smb/afp) is more convenient and faster then Browser(via https). But if you want to upload or download just a few files(not too big) to a computer just not yours, you can just use ReadyCloud(just for example). So Netgear designs these tools just for different business scenarios. You can find the best way refer to your own situation.
And for now, local users home directories just can access via smb and afp. I know devs has a plan to enhance home directories management in later version, but don't know the details and when now. So for now, if your staff want to access their home directories, in same network segment of the NAS, you can just afp or smb access the NAS share(for Mac: Finder, Command + K, afp://NAS_ip; for Windows: \\NAS_ip). If in different segment, just use ReadyNAS Remote->Shares, then login with the NAS local user.

Hope these can help you.
Thanks,
-Leia