Hello D,
I do not have a direct answer to your question. Below is an older post here from Alex, as you will see in his response from someone else looking for the requirements for a Server to support 30 players, it all depends what features are enabled, how much data is transfering to the players and how often that data is sent.
In the post at the link above he recommends building a configuration and testing. In another post I read on this subject he recommended building a server and test 10 players with the features and test data approximately the same as you plan to use in production, then multiple the requirements that worked well in increments of 10, so for 200 players, you would multiple the configuration approximately 20.
I am like you trying to determine the size of the server(s) for 100 players and how to scale that incrementally by 100 players. I am currently building out in Containers in AWS to test, where I can increase requirements, and scale additional containers with load balancers to increase capacity.
When I am done with my testing I will post the findings if I can create reliable data from the testing.
PS: It would seem that from experience they (Xibo technical team) could provide better guidelines for Server Requirements, making some assumptions on data, how often data is sent, standard set of features enabled, etc.
Thank you,
Kyle