IMO if your data model's still so nebulous that you're changing it so often that SQL migrations are a serious impediment to progress, you probably don't need any real datastore yet. You can usually figure out WTF you're going to do, broadly speaking, before persisting anything to a remote database. And if you can, you very much should.
Yes, yes, there are sometimes exceptions, one must repeat explicitly despite having already said it (see: "probably") because this is HN.
Yes, yes, there are sometimes exceptions, one must repeat explicitly despite having already said it (see: "probably") because this is HN.