Now I know the Destiny trolls and PvP whinners will -blam!- about this (because anyone with less than 1.00 kda will complain anything that makes a weapon better is unfair) We should be able to take weapons we like as drops, but got an awful roll and take them to gunsmith to swap for the perks we we like (yes we pick the exact perks we want) from the perk tree of that weapon. Now, I am not saying every weapon should be able to do this, some weapons that have curated rolls should be exempt from this. Now, these doesn't mean it comes cheap, it should cost some upgrade mods or additional ingame currency so it isn't done at a whim. Now, PvP players will -blam!- about this, but us PvE players will benefit from this because we have suffered WAY TOO much from nerfing due PvP players complaining some weapon is OP. We already get screwed on special ammo weapon swap. I think this would add some good value to the gunsmith and let us make weapons we like personal us.