KingsIsle is a business and must have revenue/income in order to continue to exist. The general idea is to encourage people to pay for the game. Adding more free quests wouldn't accomplish that.
It's to your advantage to just re-subscribe. Over the long run your paying more out of pocket cost to buy into the areas once you reach the caves anyway. Also, if you can make that one big purchase for the 1 year access go for it, then cancel your account subscription afterwards so you don't have to worry about it later. This equates to a 35.00 savings for you to use on crowns if that is your thing.