Generally, Like i want more guns and more materials and shards but don't want to hoard everything i get.
#What Should I Vault or scrap?
scarlet hill
glacial gyro
Just dismantle things with bad perks or low stat armor. Put things in the vault that might be useful (exotics, weapons with decent rolls). If you play a lot, you'll end up with a lot of weapons AND shards from dismantling...
jolly bluff
Destroy exotics you don't use too
Dim is your friend
Sort by archetype or custom stats and delete the lowest
outer jay
For energy weapons, just keep one of every element for every type and likewise for power
This is really minimalist pve thinking
In the end you might need one kinetic of every type and only the armour for the meta exotic builds
You can shard anything without missing a key in endgame pve content if you follow that criteria more or less