Luckily, none of those are key quests. I did them solo by killing off the big monster then relying on healing Palicos and Dash Juices to get the Powderstones back to base. The hardest one to complete solo turned out to be that lowly "Deliver 10 Coals" quest! If the RNG wasn't in my favor, it wasn't worth sitting around waiting for nodes to respawn so I'd have to abandon and retry. So infuriating when I'd have 8 or 9 coals but no way to mine any more. I'm glad one's optional too.HR with the powderstones are a pain.