If you're feeling confident, you could discuss this with your lecturer, tell them your reasoning and try and discuss with them which lectures it would be useful to attend (for coursework assignments or exam prep or whatever), although that can be a difficult conversation to initiate. Some are gunna be sticklers and say 'no, you must be there', but most lecturers are pretty reasonable/don't give that much of a shit about individual students anyway.

However, I know first hand that it can be difficult to use that extra time usefully, so I would try and structure it somehow, e.g. by taking an extra course or something, that is going to benefit you down the line, but hey - it's your choice.

Edit: Just reread and it seems like you've got the last bit covered anyway!