Choose for the game engine
Check whether the engine benefits from fast individual threads or can use several cores. Add memory for the map, mods and player count, with room for peaks. Benchmark the actual game version rather than relying on generic VPS scores.
Put players on a sensible route
Test from the regions where players connect. Jitter and packet loss can be as noticeable as average latency. A region choice is a starting point for evaluation, not a guaranteed experience for every player.
Protect the community and the host
Use moderation controls, patch the server and review plugins before installation. Keep administration access restricted and separate from the public game port. Network mitigation and application protection have different limits.
Back up the world
Keep scheduled, consistent copies of world data and configuration outside the machine. Test updates on a separate instance when possible. Save rollback instructions before a mod or version change affects the live community.