The brightness hardly seemed to change here (about 75% occlusion) but there was a touch of breeze at the maximum. At the 'last' eclipse I was in the UK and it was clear until about 30 mins after and then clouded over so I was able to get similar shots to yours through the clouds (but on B&W film). We used a 600mm lens + a 3x converter to project a pretty large image on a white board.
I didn't have time to play around as we were on the way to a hospital appointment. Before we left home at about 8:50 the sunlight had begun to drop as if dusk was drawing in and there wasn't a cloud in the sky. You could see the eclipse clearly beginning to happen safely through a Kodak 10H (Dark Amber) safelight filter.
On the way to Worcester the clouds built up but parted slightly when I parked and grabbed a couple of shots, using minimum shutter speed, aperture and ISO settings. So luck