To be honest,
I have some quite long time to join any high five server. So this would mean that my opinion at least for this client won't be as comprehensive as it could be.
On the other hand, interlude is pretty played client over the past years, by a very big amount of people out there, who are/were playing the game.
In general, no matter what you're going to create, you should have in mind that this is not something funny or stealthy.
Put yourself into a player's position. You wouldn't be satisfied if a server that you've like, would be shutting down for any reason. This insists at least harming.
Now if you've made the decision on which of the above clients you're going to create a server, the second thing that you need to see, is the amount of time that people will spend on playing the game
You can't target a group of people, who have not the required amount of time, while you're having a server which needs a lot of time and effort. On this case, you'll create a high/pvp rate server.
Thankfully, those clients were the most used out there, since their time released. Which means, by those years lot of server came out, trying to reach a good amount of people playing the game.
Make a little research on those things. There are plenty of examples, projects, polls, topics where they can muffle questions like this.
A poll, or a little discussion or w/e you think is going to work and reach the highest quantity of people could be advantageous. The rest are going to fall short.
I won't explain those things further, because it's pretty time consuming and useless. You can always search and ask for things like that, but if you're going to make a decision on opening a project, you should stay on your belief no matter what will happen on afterwards.
Cheers.