build out an entire featureset, get a ton of people to use it Bingo - if you can't identify an appealing, useful subset of your features that is too small for

build out an entire featureset, get a ton of people to use it Bingo - if you can't identify an appealing, useful subset of your features that is too small for enough paying customers, then you should not do freemium. You can't unring "free" once you've taught it to your customers.