It might sound silly but I think adventures were fun little side quests with a bit of story involved as well. It would be cool to see some new adventures on newer planets/patrol areas. Sure, they were basically just a high value target patrol with extra steps, BUT after completing them once, they could be made into end game content, like lost sectors. You could make legend adventures that you have to solo to drop exotics exclusive to them, just like legend lost sectors. Heck you could even make a seal that requires you to solo all legend lost sectors and legend adventures. AND you could guild it every season by acquiring the new exotic from a lost sector or adventure. As well as get champion kills, get completions, etc.