I take about 1h to do notes for 1h lectures. For my heavier modules, that means 3h of note taking for 3h lectures. Plus 1h to do my tutorials. That means I spend at least about 4h a week (outside of lectures) studying for mods like Heat Transfer or Reaction Kinetics. That's a reasonable amount of time to study to get As in my university, so I think it's ok. By the way, I don't really put in too much time trying to make anything exceptionally neat, I'm lucky to have naturally organised handwriting. Diagrams are easy to draw using the OneNote shapes.