The first part of your question doesn't make sense. Do you plan on connecting to your computer at home and then have it forward requests to cloud servers? Or are you just talking about making a cloud server yourself that is accessible over the internet (or wide-area network, aka WAN).
Assuming it's the latter, it is fairly easy to setup a decently secure file server, or ftp server (file transfer protocol), where you allow users with the correct credentials to access files stored on physical drives in your computer.
With that in mind, some thoughts:
CentOS7 may be secure, but almost every popular operating system (yes, including windows) is reasonably secure for general use given that it is kept up to date with the most recent security patches and updates.
Personally, I would look into FreeNAS, which is based off of FreeBSD, and if you have a computer with plenty of RAM, you can setup full disk encryption, configure raid arrays, and access a preconfigured control panel to access drive information or ssh into the system from a web browser.
If you want something less specialized, I have used Ubuntu server edition in many projects with limited problems. And it also allows for full-disk encryption.
I don't get the VM part, there's something to be said about security through isolation, where every application you run is in it's on virtual machine. Although for most uses this is probably way overkill. If you're interested, look into the Qubes OS: https://www.qubes-os.org/
Antivirus gets less and less effective everyday, and although I could start a flame war on why antivirus is useless on linux machines, I'll just say don't worry about it. Windows on the other hand is a different story, but even then Windows 10 has its own built in AV. But keep in mind that dynamic attacks always have a change to succeed against static defenses.
In place of antivirus, make sure your physical firewall's security is hardened, and either install a software firewall on your operating system or enable the firewall that is probably included when you install the os.
Finally, in terms of logs, any Unix system keeps all sorts of logs, and any Apache webserver will do the same. But note that logs do nothing if you aren't proactive about checking them and mitigating threats that may arise.