This is no academic blog discussion - Eric has been doing unpaid work on this project since at least June 2011 and will only see a return on his considerable investment if the game is successful. And yet, he considers and immediately dismisses the idea of NOT supporting free players. Supporting free players is "a fact of the market" because the amount of competition in the genre makes it "hard to keep people around unless you have a compelling free-play option". This decision made, Eric will do his best to optimize his server code and assume the risk that his business model will render the product literally unsustainable if the proportion of non-subscribers is too great.
Readers of this blog will know that I am no great champion of the mandatory subscription fee. However, two factors make me wonder if it would not be the lesser evil in this case when you consider A) the potential consequences in terms of sustainability and B) the fact that the one-man team now needs to take time away from making the best game possible in order to plan how to support a free and a subscriber tier, with the relevant billing and game mechanics in place. Incidentally, I'm hardly the game's target demographic - it sounds more sand-boxy and group oriented than my usual far - but the model he's describing sounds like precisely the type of optional subscription model that I generally DON'T end up paying for.
All of that said, I'm not certain I can say that his premise is wrong. Having a monthly fee is not a complete deal-breaker for me, but I am increasingly biased in favor of games whose business model does not meddle so directly with when and how I play the game. Case in point, the Secret World, which is still limping along with both a box price and a subscription fee, rolled out a free trial program recently. There is no rational reason to complain about a trial that does not cost money, but I find myself unusually irked that the terms say you only get the fourth and fifth days of trial time if you play enough during the first three.
Perhaps we really are at the point where a free to play option is actually essential because the alternative is too restrictive on players' ability to try your product. If so, perhaps Eric is going to need a bigger boat.