Kin, did you reverse #2 & #3?
I'd agree with the Common Mergansers for #1, and the female Canvasback for #3.
I'd say that #2 is a female Hooded Merganser. (I don't think a juvenile would have a yellow eye yet.) The head profile looks a bit odd, but that's a merganser bill. A Goldeneye's bill is quite stubby.
#4 looks like a juvenile Starling. It's looking at the camera, but the bill looks to be very long and pointy, plus the pink legs narrow the choices.
BB