"...that PNG would not lose resolution in editing, particularly in rotation of image "
Nonsense.
As far as enhancement goes, depends on if you shot in RAW or JPG (but I guess the A610 doesn't do RAW?). In RAW you could virtually change anything, starting with a slightly warmer white balance maybe, over to less contrast and/or highlight recovery etc.
On the JPG you could add a warm filter (In PS CS2 somewhere under Image-> Adjustments ->)
I'd also crop off about the lower 1/4 to get rid of the centered waterline |