I have a new Colt LE6920 M4. I am shooting it instead of leaving it in the safe. Right now I have a cheap $200 scope on it with red lighted cross hairs. Eventually I want to get an ACOG for it with the donut  hairs. What I also want to do is mount some accessories. I would like to mount a very light  in weight flashlight on the the right side of the rifle. I would like to mount a targeting laser on the bottom for close home defense situations. I would also like to mount a forearm grip on the bottom as well. Obviously I am going to need a rail system as well. And with that in mind I would like the eliminate the front sight all together. Thats pretty much it for the accessories. I have done quite a bit of research since I got the rifle but naturally I am still confused. So I have a few questions for the experts here.
I would like to accomplish this with adding the least amount of weight to the rifle.

What components do you all reccomend for this plan with keeping quality in mind? I dont mind paying $$$$ for quality stuff. Which gas block will work the best with the 6920, hopefully someone else has put one on their rifle. With the above mods to the rifle what do you think it will weigh without a clip inserted?

All of the help here is GREATLY appreciated. You all are the best.

It would be a mistake to remove the front sight....my opinion.  If you don't like it, I suggest purchasing a different upper.  If optics fail, what do you intend to use as a reference point with no front sight?  You have the right idea on keeping the weight down on the accessories.  You will have to decide if you want a free floater rail or nonfree floater.  Then decide from there.  I am in the minority in that I would like to have a nonfree floated rail.  I want to be able to remove the hand guards easily and at any time.....but there are a lot of guys liking the free floaters.  I'm sure they will chime in.

Quoted: I have a new Colt LE6920 M4. I am shooting it instead of leaving it in the safe. Right now I have a cheap $200 scope on it with red lighted cross hairs. Eventually I want to get an ACOG for it with the donut  hairs. What I also want to do is mount some accessories. I would like to mount a very light  in weight flashlight on the the right side of the rifle. I would like to mount a targeting laser on the bottom for close home defense situations. I would also like to mount a forearm grip on the bottom as well. Obviously I am going to need a rail system as well. And with that in mind I would like the eliminate the front sight all together. Thats pretty much it for the accessories. I have done quite a bit of research since I got the rifle but naturally I am still confused. So I have a few questions for the experts here. I would like to accomplish this with adding the least amount of weight to the rifle. What components do you all reccomend for this plan with keeping quality in mind? I dont mind paying $$$$ for quality stuff. Which gas block will work the best with the 6920, hopefully someone else has put one on their rifle. With the above mods to the rifle what do you think it will weigh without a clip inserted? All of the help here is GREATLY appreciated. You all are the best.

Well couldn't help but help you....it's called a magazine not a clip heMy suggestions
-surefire light
-any free floating rail system (I use the Ras II with the hump)
-whatever grip you think looks best/feels most comfortable if you can try them out...some of them hold batteries which is nice...check tango down, knights, their's others.....
-for a laser I'd probably go with the OTAL...it doesn't mount on the bottom but supposedly it's good sh1t (supposedly)- unless you can afford a paq-4c

I say skip the laser.  It has a niche, but is pretty useless in the everyday.  Unles you are using an IR laserr with NV, you will find the laser more of an annoyance than anything else, IMHO.  If you just absolutely have to get one, then the OTAL mentioned above, or any other laser made by Laser Devices) is about the only quality direction to go in for a visible laser.

I say keep the front sight or get a folding one, but I would say keep the fixed for simplicity's sake.  Never, ever go without irons.  Period.  Don't try and outfit your gun like something in an action movie.  If you do, you will find the stuff that you have left off is the same stuff you will be wishing you had kept and some of those cool looking toys will end up being nothing more than very expensive paperweights and conversation pieces.  

The flashlight is a good idea though.  A very good idea.  Be sure to look at the lights from both Surefire and Laser Devices.  The SF lights will be more modular and expandable/changeable.  However, the LD lights will be of equal quality and ruggedness for a much lower price, albeit without the modularity of SF systems.  

As for optics, you might want to look into an Aimpoint or an EOTech.  You mentioned close quarters and home defense.  So unless you have 300-400 yeard hallways, the EOTech or Aimpoint would be faster for use in that situatio, although YMMV..  It would be cheaper than an ACOG as well,  Of course, you could always have an ACOG and an EOTech and have them on QD bbases so you can switch optics for different jobs.  

For optics, I recommend you check out EOTech. I was set on an ACOG until I did some research and did the touchy feely stuff. Go find a dealer that has them and check them out in person. Then make your decision. I got an EOTech 512.65A Rev F from Texas Tactical for $282 shipped. Much cheaper than the ACOG and aims faster too IMO. Don't eliminate your front sight. What are you going to use for backup if the optics fail (Murphy is always smiling on those things) Leave the front sights alone, get a rear BUIS (many options). Skip the laser. They're cool and techie but not much else. They also give away your position.