Quick way to a solid AR that is shorter and lighter:

Go to a shop and grab a complete pistol lower with an sba4 brace. If they don't have one, try a gun show for the same. If not there, order online from Anderson arms, complete pistol lower. Shipped to a local shop.

Get on palmetto state armory site and purchase an 11.5 upper - 1:7 twist.

Snap them together, upper and lower when they arrive.

Pickup a sig Romeo 5 XDR red dot - it's the model with a AAA battery and circle over dot option.

Then grab an informed wml light to attach to the end of the rail.

Finally grab a vickers sling or magpul ms4 sling depending on how you want to attach it and what the rail options are from the factory.

You now have a solid battle rifle covering all the basics that is lightweight and easy to maneuver without shooting the big fireballs out of the front like a 9-10" will.