First things first, sit further forward. Arms on the foredeck. Dragging the transoms around is very slow.

As you said it looks like you are choking the main, but only a little. Ease mainsheet a fraction and pull on some outhaul, a gap of about four fingers should be maximum, one finger minimum. It looks like you have about a hand-span gap in those photos.

Upwind in light stuff the key is to maintain speed.