This early '70s rifle has had added an old big/small aperture flip rear sight, a tritium front sight, a no trap buttstock, a chromed no-forward-assist-cuts M16 bolt carrier assembly, a three prong flash hider and a push pin in place of the big double headed screw.
So it seems possible to "accessorize" without adding weight or reducing utility! I do prefer the round handguards, but that's an easy swap, and again doesn't add weight.