I wouldn’t worry. At the worst, he’d stop adding to it. Coronium is highly capable, solid, and functional. Also, once you’ve built your base (unmodified) server, you can always make a copy as a easy starting point. Then you’ll have it forever.
In any case, you’ll still have to choose the best solution to meet your needs and there will be investment in learning.
re: Your Game
Aside from the primary interaction (turn based exchange of data), consider other facets of the MP experience like:
- Score keeping
- Account creation.
- Game management
Also, I assume that in your concept of turn based, the players are all playing at the same time and that turns are not indefinitely defer able (I’ll play my turn next week.) The latter requires a totally different kind of solution.
@ all other reader 
I hope some other folks respond with answers re: their own experience and knowledge on this.