Like Allods said, if you dont want to play with ppl astral is pointless, gearing a ship and solo sail is hard and doesnt worth the effort, trading refractory for loot is was less time/gold wasted.
I do astrals cause they are pretty easy usually!, AND, adressing the loot and mobs, you get more stabilizations, crystals for the ship, ship parts (usually green, yeah) and i'm using those refractors from FD (cause i'm there currently, 46k gs...), the ones with 50%, cause they are pretty cool, they seems like you are using the 100%, and i know that may sound kinda stupid, but i tried opening boxes with both and i felt that: 50% ref = 100% ref WHILE USING FOR OPENING THE ASTRAL BOXES.
I can solo/merc: Jeer's House, Emerald Isle, Reflection of Irdrich (love this one cause of the extra box you get), Catacombs, Green Maze and bounch more of them that i don't remember atm. I'm saying this cause it's not fair that some of them are pretty doable with mercs while some of others are kinda hard and unfair (the damage the acid deals on Desaardet... why?).
Gonna keep trying astrals tho... faster and easier SOMETIMES u.u
Btw, who usses the R button anyways?... gonna try it, could work. Tell you later, thanks