I've gotten an idea for a theme for an online, web-based, energy-based sort of game, ala Utopia/Kingdom of Loathing/Minethings. The basic idea is that players will be randomly sorted into groups of a dozen or so players and will compete against each other for about 2-3 weeks before the game resets and things begin again.

My problem is that while I have a strong theme for the world, I'm having trouble devising mechanics that I'm confident will be fun. For single player games, it's easy for me to just play it myself for a while and see if I'm enjoying it, but for a group game that takes a few weeks to play a round of, it's difficult to easily play test, especially without a lot of help.

I've been thinking through ways to try out game ideas. My basic ideas are:

1.) Paper-based mock version. Drag one or two people together and try to play the game on paper. See if it makes sense.
2.) Just try and build something that seems like a reasonable idea. Attract a few dozen early players somehow, and tweak things heavily until players are happy.
3.) Start with an almost boringly small number of game features (Welcome to game! It's Wednesday. Press A to spend today helping yourself or B to spend today hurting other players) and very slowly add features and pay attention to feedback.

Has anyone else had much experience crafting a competitive online world? I honestly have no idea how a game like Utopia is designed or play tested.

One of my old professors was a famous board game designer, he spoke a lot on video game design, and always reccomended that you create a paper-based prototype of some sort before you begin work on the "real thing." You shouldn't just see that "it makes sense," as you say, but also that it's super fun to play. If it's not fun on paper, it won't be fun on a screen.

The problem with #2 and #3 is that it requires getting a bunch of people that you don't know to do something of their own accord, without compensation. Unless you already have a decent batch of people who would be willing to do this for you (friends, or a strong social media following,) then it's unlikely to work in the way you would hope. You'll just spend a lot of time spinning your wheels while you wait for feedback that will never come. If you make a board game or card game, you can play it with some buddies and get instant feedback before you put any work into the tech side of things.