Wow, so much Blinks 
I think that is very much traffic. You should better reduce the intervals. Perhaps 5min for status and 15sec for motion alerts.
And your diagnostics report (it’s your I think) is showing a lot of http 403 errors (not allowed/rate limited). Your tests are raising the rate limit, I hink. I can see that some image request are resolved in 5sec (battery camaras need some time to wake up, connect, take snapshot and sent it, the mini cameras are much faster). After some tries, the limit is exceeded and you get 403 errors. That’s why you get error messages in snapshot view.
If the error in snapshot view appers after 10sec, the API is ok but the camera did not return a new image.
In the error occours directly, the API is responding with a http error.
You can see the errors in the device settings of the account device (API state). You can set the alarm waiting time to 0min to see the alarm on the tile. Don’t create a flow in that case. It will fire for every call 
. A flow is only good if you have a waiting time for the alarm (1 or 2 min).
I don’t know a possibility to change the order of device views. It’s predefined I think.
In the WebApp, the button is shown first, but at this moment, the image is requested, too (perhaps only if no image is present).
So I hope it will be usable for you and the big amount of devices. After the first play time it will be ok I think. I don’t check the images in the Homey device. I use it for automations like activation/deactivation of motion alerts and arm/disarm based on time or local situation (Open the doors will deactivate the camera alarm if Heimdall is disarmed to avoid too much recordings. I think this will be the main advantage of the Homey app.
