In my experience customers don't want to hear about all the issues we deal with (lib updates, …

It's interesting that in your thoughtful survey of alternatives, you don't consider simply challenging the assumption "and provide updates forever". Subscriptions do indeed fund perpetual development in a way that one time purchases don't, but the implication that comes along with that is that features are to be added along the way. If you only released maintenance patches, you subscriber satisfaction would dry up really darn fast. So now we have this model where publishers charge subscriptions so that they can keep their business stable or growing, and subscribers are demanding features be added so that they're getting value for the ever-growing total cost of ownership. And what do you get from that? Feature Bloat. The subscription model insists that successful products need to continually grow their code base, complexity, and feature set. The idea of stable streamlined applications tha…