More importantly I would love some course that challenges a senior developer in not only impl. coding but also in architecture and design beyond the famous fad architecture in Android world as of now
Sorry, just noticed this. Arguably, there's only really one proper architecture today: UI (View+ViewModels), Data, and possibly Domain in between. Most of the others seem to have more cons than pros. This is a great guide on architectures, more up to date than most articles on the topic: https://developer.android.com/topic/architecture
The previous linked tutorial covers coroutines well enough to do things with it. If you want to go further, I'd recommend figuring out how to combine Kotlin Flow with Compose; neither Compose nor Flow really shine without the other. Sadly can't find tutorials on this either. Planning to open source some templates some time this year.
More importantly I would love some course that challenges a senior developer in not only impl. coding but also in architecture and design beyond the famous fad architecture in Android world as of now