After thinking more about the process, I also found that it is quite cumbersome. Especially in the beginning, it takes a lot of time to create new cards. And because of the effort, most people will probably not attempt this. But after a bit of training, I can create new cards in a matter of seconds. When you've already opened all the tabs to Dictionary/Google Images/Forvo/Reverso, it's actually simple enough.

But yeah – I'm still thinking about how to automate the boring (i.e. non-valuable) part.