How would you invest your time?
I'd do pretty much what I'm currently doing. I go through the text first, lingQing all new words. Then I reread the text while listening to the audio at the same time. I then reread the text while listening to the audio a second time. In total, this results in 3x reads and 2x listens. I very occassionally go back and read + listen to a previous lesson, which I listened to several days/weeks ago, just to mix it up. The pure listening (of the material I've already studied) is only done when I'm washing the dishes, cooking, driving, going for a walk, etc. You can really get in more than an hour of study each day this way. This strategy is only at my current level of 1,591 known words. When you become more proficient, I would do less repetition. Once you are C1, you would be doing predominately extensive reading/listening (so outside of LingQ). Or maybe you're practising pronunciation or speaking or writing. So it really depends what level of the language you are up to and what exactly you're focusing on at the time. It's good to occassionally mix things up too, just so you don't get bored. The start of the language journey can be a real drag, that is, require a lot of effort to do everyday and power through the repetitive task of always lingQing easy and sometimes not-so-interesting content.
I think I'd have to "learn" what would work best for me with an hour a day. I've kind of figured out my 15-30 min a day...and if I have more time on a given day it probably mostly gets filled with listening and some extra reading.
I would probably start with a half hour of dedicated reading and the other half hour with listening, either alone and/or listening while reading.
I would probably change things up a bit though. I'd like to be doing some more writing than I'm doing currently, so I might dedicate some of the days or hours to that. Probably some speaking practice too.
At my A1-A2 level, I'd spend 30 minutes reading, 15 minutes listening to mini stories while reading the text and 15 minutes watching video in target language native speaker and target language sub titles (like "Easy German" for example)