gotta be frugal with exotic upgs if low on shards..... don't go 380 -> 381 -> 382 ..... etc unless its some sort of a light/damage breaking point (like 370/380/390 for the raid). If you favor a certain exotic, always have a backup of something else in slot until you have the shards/light to hit the next point. Break down any exotics you don't use, or probably won't use for a while... Theres some fun guns out there like telesto and 4th horse, but if you're hellbent on light/upgs/shards, they can wait