Assuming 7nights = 7 park days for you...
7n No Hopping = 4 MK days with wishes + 3 Other Park Days
5n With Hopping = 5 Park Days with wishes.
So by cutting 2 days off you would get a max of 5 nights of wishes but 2 whole days less at the World.
By cutting park hopping, you can still get 4 nights of Wishes, thus 4 MK days and still have 3 other days for AK, DHS, Epcot. Plus with 4 MK days, you could have some down time on those days.
Personally i would rather have more days at the world, but that's just me.
Along the same lines as this post, if you are going in October there will be 3 or 4 nights that MK will close early for MNSSHP, so you won't be able to watch Wishes those nights. I would skip the park hopper option this time if I were you. We're going the last week of September into October and 4 nights are MNSSHP nights. We decided not to get park hoppers this time, in order to save the $300.