Yes, the grind is real. The best way to get weapon parts is definitely strike playlists, with the drops throughout the mission, and engram rewards at the end of each. But I hate this. The point of leveling up all of this stuff is to enjoy the end game content. But raids and PoE don't give any sort of engram/glimmer drops (aside from convincing 5 others to farm gatekeeper, I know, I know). I can only assume they kept this out to prevent farming? But that just forces farming in other story areas, so what's the difference? Ugh, IDK. I just need weapon parts.