I have never seen any software program that would estimate trajectories with arrows. If there is some software, I'd like to see it also.
Compared to projectiles fired from a gun, arrows are a whole different animal. IMO
From my experience, a 425 gr. arrow that is flecthed with three 5" feathers may have a different trajectory of one that is fletched with three 5" vanes at 40 yards. Add to that, with all the different flecthing possibles, it would be tuff to give anything more than a guess. The point can make a difference also.
In regards to your querry about arrow speed, are you asking if 50 fps will flatten out your trajectory at 40 yards? The answer would be YES. But, it could be very slight. Or, it may be very noticable.
Take a kid with you. Show them the Great Outdoors. Pass it on.