Glimmer should be left alone. You can't buy your way through progression by design. It's a core reason there's no trading, no auction houses, or any player driven economy to speak of. The limitation is deliberate by design. It forces players into the content if they want to obtain a goal. If you provide a route to players that circumvents the content required to progress, you're literally removing that content from their play experience. Yes, you have to do the content to get the materials to upgrade whatever it is your looking to upgrade. That's how the game creates the incentives to play it. Glimmer is just not that important to progression, and that's a good thing.