Let me try this again...
First, let me apologize for my first couple of comments. Since you already purchased the Sport, they weren't helpful to you.
Now, let me try to give you a few things to think about. You have said that you want to use the rifle for night hunting and home defense. Those two uses are more than likely going to require different setups.
For hunting, you will typically want a high output light with a spot beam to increase distance the light will reach. This type of light will not be good for indoor use as it will be too bright and bounce off surfaces, degrading your night vision as well. A wider beam is better for indoor, close use. The hunting lights will typically be bigger, with larger reflectors than a tactical light. Also, don't forget about filters... make sure any light that you choose for hunting either used color LEDs or filters are available.
As far as using the light as an aiming tool, that will take a lot of practice. The Streamlight that I have throws a center focus beam that covers center of mass on a man size target at across the room distance (10')... across the room and down the hall the center beam is now huge... I would have to practice at known distances to know how big the center focused beam would be and where the round would impact within that beam. Not saying it couldn't be done, but I can be more accurate with my red dot with less practice.
You also mentioned accuracy as a benefit of a free float. That advantage isn't going to come into play at inside the house distances, and probably not at hunting distances either. If you are looking for an increase in accuracy for your use, you will be better served by optics and trigger. Spend money for those over a free float hand guard.
Speaking of optics, that is another difference in set up for hunting and home defense. Typically, hunters use a high powered optic for magnification, where as in a defense gun, a red dot is more beneficial due to faster target acquisition.
I use my AR for hog hunting. I use a red dot, as I want fast target acquisition... my hog "hunting" is more eradication. I want to be able to put as many aimed shots into a group of hogs as I can before they all scatter. When I am actually hog hunting for meat, I use my bolt gun with scope. Pick the one I want, hopefully make the perfect shot that drops him where he stood and not have to try to track him down.
So, long story short, think about what you want... a hunting rig, or a home defense rig? There may be some solutions that will allow one gun to do both, but they will be compromises and have short comings.
If it were me and I wanted to lean more towards a defensive rifle, I would get myself a good red dot, a Magpul hand guard so I could attach a light, and ammo.
If I was going for a hunting rifle, I would spend my money on good optics and a trigger upgrade. A free float rail would be low on my list when it comes to getting the most bang for my buck.
Good luck with your decision.
