I rely heavily on the ammo parts and would like to expand that feature to buy armor materials from the cryptarch. What I would like to see/suggest is a regular rotation at the gunsmith. That whole line of material/consumable options should just rotate. There are 6 spots for 7 items: Primary, Special, & Heavy Telemetries, Primary, Special, & Heavy Ammo Synthesis, & Weapon Parts. Each weekday one random item on that list will NOT be available, followed the next day by a different item not being available. I think that system would be plausible.