Is 1600 grafts (specifically 3200 hairs) enough for the front area to provide adequate density? (Photos)

Photos cannot determine if you would be a good candidate for surgery.  You need an examination and the doctor needs to understand your goals and expectations.
You need to have good communication with your doctor to understand what your end result will look like. 
Someone with your hair loss pattern may be perfectly happy with 1500 grafts, while others may not be happy even with over 3000 grafts.  You also have to realize one surgery may not be enough.  To add to the confusion, straight black hair on fair skin results in a thinner appearing outcome then someone with curly blond hair on fair skin.   I hope you can appreciate there are many factors to your end result than just a "number" of grafts.

A great first step would be an online consultation. Often you can submit photos to top hair restoration surgeons for a complimentary evaluation and assessment. This should help lead you in the right direction. Having multiple consultations with different doctors will let you know your best options. 

Yes, 600 grafts will  be enough for the front area to provide adequate density.Hair transplant can be an option for forehead reduction,  correcting  receding hair line and asymmetry on your frontal hair line/forelock.I advice you have a FUE; you would get the desired hairline in just one sesssion of dense packing hair transplant.