A perpetual fallback license model is the most customer-friendly I've encountered. It's effectively a subscription model which doesn't have the customer losing access to the software when they stop paying their subscription. They would simply have access to the most updated version at the time of their subscription lapsing.
Having features locked behind a paid subscription in software that's otherwise free is probably next best but I find myself being frustrated by this more often than not.
Having features locked behind a paid subscription in software that's otherwise free is probably next best but I find myself being frustrated by this more often than not.