I love my Scathelocke: but Forsaken gear has tactically (on a statistical level) made the pre-forsaken gear defunct for near/ end game play.
I would suggest producing a mechanic (through Banshee / Gunsmith) that allows the use of resources to roll a 2nd perk onto pre-forsaken gear.
A one time roll with no option of re-rolls (as to not bias away from Forsaken gear): maybe only being allowed if said weapon is Mastercrafted as to not take too mmuch attention away from the Forsaken gear (as Bungie seems to want a greater focus on it for end-game.
Still. I love me ol' Scathelocke and I imagine others would like the ability to continue using their older weapons into end game (without the tactical flaw of a singular trait).