I've had a quick look at your site because I'm currently using DO and Vultr with a PeerVPN[0] setup to connect the individual hosts - which brings me to my question:
Is it just a static website or do these instances communicate with each other? If you do, I'd like to ask if you use a VPN to connect them (and which one)?
I'm relatively happy with PeerVPN (with one or two rather minor annoyances that most likely can be solved if I actually spent time on them) but am always curious about alternatives.