It is a minor "farming marks" tip, but I like to XP level all my legendary weapons to half or more before dismantling. You can get 5 legendary marks opposed to 3. I will do armor if I have a lot of bounties to cash in, but with weapons, just pop a telemetry, then burn a few motes of light, and you are getting more marks per dismantle. I am swimming in motes of light and telemetries are cheap so it is a good way to squeeze some more marks out of gear that you plan to dismantle anyway. Also a good tip to level up gear you want to keep at the same time so the MoL are not just going to trash purples.