I play on PC, maybe thats the difference. I think most problems are because of the enemies disapearing into the floor or into the sky. The game doesn't let you continue if you are still in combat so NPCs wont't spawn and quests don't progress. I was able so solve a lot of my problems by leaving the planet and landing again. Then the enemies reset (and mostly spawn properly) and the quests work again. The only thing i couldn't solve was the questgiver in the town on Eos, he/she's just not there. And resetting those fights mean i have to do them all again.
Still, i have fun with the game.