Practicing sketching - Feedback appreciated

Hi guys.
I got some great feedback the last time I posted here, so i figured that I’ll try again.
I haven’t sketched as much as wanted the last year, but it is getting better.

Below you see a collage of the more recent of my sketches.
It would be nice if you could spend a minute, give me some critique.
What do I need to work on? How should I challenge myself? What should I stop doing? What should I continue doing?

Your feedback is much appreciated.
Best regards
Esben Oxholm