App install stats ?

Not having the ability to screenshot on the Bangle feels like a big issue

For most apps like clocks using the emulator would probably work, but maybe "adding screenshots is a good idea" should be documented a bit more? It's easy to overlook for people who just spent a lot of time staring at the app while developing it.
(Somewhat off-topic: a nice addition might be some way to specify a single screenshot per app which is displayed right away in the list of apps.)

Download stats would definitely be nice to see, but you run the risk of a feedback loop where people keep downloading the most downloaded apps.
Maybe the About page could get a button to "Participate in survey", to submit currently installed apps? That way it's opt-in, and the idea is that people submit their setup once they are happy with it, so you won't count e.g. five HRMs per user while they try them all out.
(And because they are submitted as set, you could even suggest apps "often used together")