I think this is totally a fair way to do this. I know HN sometimes grumbles about this type of pricing, but totally get it. You’re not taking anything away, you’re just charging for new features after 1 year they paid. They don’t lose access.

(It’s like back when we had Photoshop 5 and then Photoshop 6 came out).

As long as you mention that security updates will be free, I think this is a good plan. It’s how you get indie devs paid to keep working on products.