Right. My idea is a URL builder for Home Assistant as one of the providers (alongside internet request). To make it easier to generate the URLs. The URL builder should be able to query Home Assistant's API to return valid entities, etc.
Aside - I don't type JSON in the app. I agree - too clunky. And the input doesn't seem to scroll back and forth well. I generate the text on my PC and use Pushbullet to send the correct text.
If you don't like to put your api password in the Flic app, you won't be able to use the API anywhere. It's used by IFTTT, Alexa, etc.
But, yeah - you're looking at essentially 3 http requests per button (not multiplied by # of hubs). For instance, call a script like:
Just make sure you use application/json. It's not a big deal. You can trigger anything that HA can do with an API call.
The Flic integration in Home Assistant still requires you to install the Flic service outside of Home Assistant.
The "internet request" provider has been working well for me. I think that, rather than integrate from the Home Assistant side, it might be more straightforward to have a variation of "internet request" that helps you build your API call. Let you declare your password (to be sent in header or URL), pick services (they can be populated via a REST request to HA). Basically, something that acts like the services dev tool, but from within the Flic app, making it easier to enter things on your phone.