Palehorse: I compared the Viper 2x7 with the Prostaff 4x32, and I saw a significant difference between the two, optically, in favor of the Viper. I assume it would be the same btw the Viper 2x7 and the Prostaff 2x7 (which I have never owned). On paper, There is also a significant difference in FOV at same mag, in favor of the Viper, by 25%. If I had neither I would choose the Viper.
However, every pair of eyes is different. You already have the ProStaff, which is a bit lighter, and minimally more compact. I think that most everyone will see a difference between the two. I am not 100% sure that everyone will see a difference significant enough to upgrade.
I have also never hunted back East, and I am not sure of the hunting conditions there. Beyond the FOV, I would say the difference is more significant in terms of discrimination/ clarity, and wider sweet spot - I feel that the low light difference is at most worth a small number of minutes if any.
As for the reticle, as I imagine, you know there is a wide preference on this site for the C3 reticle. I, on the other hand, have 2 BDC 2x7s, which I prefer because I like the wide stadia and the extra dots, to shoot at a longer distance at the range with my hunting reticles. But - that's me:-) In fact, what I have read on shooting literature (cf specifically Whelen Townshend) tells me that a C3 reticle would faster to shoot and more accurate at shorter distances.
Hope this helps - take care and good luck.