Sorry, chief. I've been a macOS dev for 10 years now. I think charging a subscription for a menubar app with a singular use-case is just the absolute worst. "not one time payment because I don't know what would the right price be for supporting an app for years to come and still have people willing to pay for it" The right price would be about $5-10. If you want to be kind, $0.
Even the simplest apps end up having problems, even the perfect one can break when something in the environment changes. Working on even the simplest app is always a full time job, not because you write code 40hr/week but because you need to have you attention on it, retain the information about the architecture and more importantly the "gotchas". If you don't, you will end up spending hours and days for the simplest things to study your code and re-discover everything again so you can work on it.
Or maybe that's just me, maybe other people can work on 10 projects making simultaneously and fix a code they wrote months ago in seconds. If that's the case, those people should make all the apps so we can use em for cheap or free and we can go do better things with our lives.
I can experiment with the subscription pricing though.