I noticed last night I only had about 15 minutes left of the 7 hours I get as a free player. (I had intended to leave my character idle for a bit so my clay cauldron could boil. It ballooned into about an hour due to extenuating circumstances).
Now, I'm not asking for a refund of that wasted hour or anything. At the same time I absolutely refuse to "verify" my account; $15 is too much, even for all the years I've been here.
BUT, here's my thought: other games such as Runescape, and of course games by other "entrepreneurial" Vikings (such as Rovio) have advertisements on their games. Runescape IIRC has banner ads over the game screen while the game's running. And in order to unlock levels on Rovio's "Bad Piggies", they make you watch videos from their sponsors.
Perhaps you could strike some deals with some advertisers for more money - and perhaps be generous enough to give "free" players (since we'll be seeing ads) more hours?
FURTHERMORE, realising not everyone wants ads, perhaps agreeing to see ads could be an opt-in programme? i.e, we agree to have ads attack us (say before we login to the game) in exchange for an extra hour or three every week?
Like I say, those moneygrubbing Finnish bastards at Rovio do it, and I still love Angry Birds and Bad Piggies. (I am NEVER removing them!) I would not mind if my favourite moneygrubbing Swedish bastards did it, too.
EDIT: For clarity's sake, I'm suggesting ads in addition to subscriptions, not as a substitute for it. If you want to shovel money over to the two Swedes, I got no bones. But I, for one, would not mind sitting through a few ads to get some perks.