Just so you have a little more information as comparison and the reason of why I estimate that CPX11 would be enough if it has just a little bit more of Disk Space.
My community receives (daily):
- Registered users visits: 500-750
- Anonymous users visits: 2300-3000
- Topics: 2
- Posts: 10-30
I’m running a 1vCPU and 2GB RAM setup and haven’t found any performance issue.
The issue is (as always is) that each person visiting at the same time will need some server resources (CPU/RAM) if you use a CDN this needs reduce greatly as most of the load of finding the files and shipping them to the user is offloaded of your server.
Now, the specs of your server will be tied to your disk space and to how many users decide to visit the site at the same time.