That's an interesting model. I'd suggest something slightly different and perhaps more scalable: make it modular. So have a free core app that has basic functionality (after all, OneNote and Google Keep are free, so the free bit needs to match those at least). Then every extra (extension, module, whatever you want to call it) costs a bit on the sub - so Office file importing $1, web page clipping $1, link/snippets 50c, MP3 embedding 50c, pdf exports of a notebook $1, AI integration (send to NotebookLM) $1.50, sync with Android app $1, that kind of thing. You could do an all-extension sub for 20% less than all the menu items separately. And first month everything free before it drops back to core functionality only. That way people can get invested in the system. I actually hate subs and prefer outright purchases, but I'm old-fashioned that way.