Add class exotic items to the reward pool for the Pale Heart on legendary story completion, or add them to Xur for everyone, or add in a solo instance of the Duality mission (team player with an NPC, modify the mechanics to support).
You're on for a beating with this post.
All the screaming gate-keepers will attack you as you are asking to get something in a different way to how they got it... This absolutely cannot be allowed as it devalues their achievement.
Usual comments will be:
It's a multiplayer game!
(No it is not... it is a 1st person shooter with elements of MMO... as per Bungies own description... the fact that all campaign missions can be completed solo and only end game content requires a FT is lost on them.)
You're just being lazy!
Get friends!
You're entitled!
Etc. Etc.