Furniture really doesn't do all that much. I shot the M16, A1, and A2 just fine.
What I noted with the A2 was that the LOP was a tad longer and the grip annoying - to me. It didn't make any difference in accuracy, tho, and carrying it for two weeks at a time in the field it didn't have any affect.
What we like is another matter. I built an AR with A1 stock, Troy grip, and A2 rifle handguards. I couldn't find a smaller grip, the Troy works for me. After I used it, tho, I found I was doing a lot more stand up shooting - I don't normally go to prone deer hunting, and I don't read or see many others doing it that way, either. Wearing a insulated winter coat made the issue even more noticeable. While I thought the A1 was everything anyone would need - it was based on prone position qualification and face in the dirt infantry tactics. Not so much for it's current use.
I switched to a carbine stock and the adjustability is nice. It can be shot in warm weather or cold with the same cheek weld - the LOP is different, tho. For the actual buttstock, I got a Minimalist, because I'm not doing three second rushes hitting the ground or getting into combatives with it. And no, I'm not putting all sorts of braided tribal paracord on it. It doesn't get hooked on things.
That left the handguard, and as lightening the carbine left some weight on it, off comes the clamp on front sight and handguards for an Apex Gatorgrip. I'm using a red dot, the extra burden of iron sights was something hunting rifles left behind in the '70s - as did I when I bought a first Gen Aimpoint. Should lose at least half a pound overall right there. The rear sight is going, too, fortunately I bought a used carry handle M4 sight and simply cut it down. $35 was all it cost compared to $80 and up for a lot of the aftermarket.
It's a noticeably lighter, swings faster, and isn't as muzzle heavy now. For the money it could be a lot less expensive - fore end tubes can be had for less than $100, but it suits what I wanted.
Changing the furniture should have some gains involved, we are well past the M4gery fad that hyped up milspec features at the cost of more weight and arbitrary functions we don't really need.
Don't miss a bayonet lug at all.