Upon further reflection, I realized that the revenue constraints are even lower. That $15 would be reduced by taxes and engine fees by about 30%. If we further speculate that staff and other operating costs would be a further 30% and suppose a profit margin of %10%, the final piece of the pie available to pay for Spatial would be in the vicinity of $3.50 per month per player.
As your revenue model is based upon usage:
Neglect, for the moment, all calculations of fees for persistent, non-player workers, even though the number of such workers in a large open world would be significant.
Assume launch month obsessive compulsive behavior. A hypothetical average player would play approximately fifty hours per week for 200 or more hours per month.
Lets further presume that our game is a niche, low population game with 1000 active subscriptions.
If my math and assumptions are anywhere near correct, that’s 200,000 hours of playtime for $3,500 per month.
That’s 0.0175 US cents per hour per player.
If the piece of the pie available to Spatial were even less, say 10%, then per player hour revenue for Spatial would only be 0.0075 US cents and total revenue only $1,500.
If, in month two, players spend half as much time logged into the game, then while subscription revenues remain constant at $15,000 per month, metered Spatial costs due Improbable would fall by half, more or less.
It will be interesting to see how your actual charges plug into this speculative formula.