11: You must cut.
Remember the proverb that says to 'extend from a crosscut'? In diagrammatical form, it means that black wants to play in one of the circled places.
If you crosscut, you already have the extension at M17. In other words, M17 fits perfectly with a crosscut. O16 is the Joe Paterno of go stones. Instead of putting up a proper fight, it looks the other way, and lets the bad guys do what they want, and M17 is abandoned.
19: Good!
29: Just the simple hane will do fine here.
37: There are two cutting stones: N13 and N11. Which one is more dangerous to you? Both of them work to isolate your M12/N12 stones, so in that respect they are equal. But N11 cuts off your side group which is quite safe, whereas N13 cuts off your corner group which is not quite as healthy. So you want to play on the northern part of the fight, not the southern.
Hane at L13.
49: M16 kills his three stones.
51: Good! Late, maybe, but good.
53: L15. Lock him in, don't force him to run. He is in trouble, so he wants to run. Don't force him to play the moves that he wants to play.
61: You have two heavy stones at K16/17. Something like F16 or K18 is interesting. Or even K15.
67: Complete aji keshi.
79: F3
103: M6 starts to enclose a big chunk. There is no point in chasing a cutting stone unless you can forcibly capture it. Just chasing it while it runs simply makes it stronger.
109: N5 keeps you strong and connected. Note that you have G4 waiting.
125: Nice move. G8 might do it a bit better, though.
145: B13. The cut can be protected by a short ladder.
161: It is a snapback. You don't need to play there. Play K18 or K14 and something dies.
Overall, I'm seeing a new character to your play: serious and sustained attacks.
Just work on technique and you will be 5K overnight.