I don't know being able to upgrade gear from T0 (old guns) up to T5 in some way would be more in line to the (RPG) part of the MMORPGFPS looter shooter thing (or equivalent) destiny is...would encourage gameplay rather than scare people away from it...having seeable and tangible progression that you can keep with you is rewarding and organically encourages active play... people will naturally get bored with a gear set and play style over time and move to other things is an individual choice...forcing players to play outside of their preference is bad... Intentionally locking in a meta requiring investment just to drastically change it in the next season just to do it again is torture equivalent of Sisyphus and his boulder....