Request - Ability to have friends help you level trust members

I like the trust system and like how good the NPC's act. I just don't like to play solo and that's just a personal preference of mine. I would like to level my dungeon trust members but I don't want to grind hours and hours by myself. It would be nice if you could do trust dungeons with 1 or 2 of your friends and fill the last slot with one of the party leaders trust npcs. This would allow you and friend to play the dungeons together and level your trusts and learn mechanics together. It would also be nice to say once you get Thancred to 81 then switch leader to your friend and level their Thancred to 81 cause they are now party leader and was able to fill with their trust people.