Cleaning my overstuffed inventory

I'm trying to get back into GW2, in large part because it's one of the few MMOs I've liked that actually works well under Linux.

For a frame of reference, my main was a Nord Necromancer with ~33 mastery points, and the three easier-to-acquire mounts. I completed the main story and HoT, and sort of drifted out in the middle of PoF for like two years. Just bought the EoD expansion while it's on sale.

I've got one 20-slot bag and four 15-slots, and maybe 1-2 slots free at any given time. I suspect my problem is less "bag space" per se, and more a hoarding tendency-- crafting items, "turn it into some NPC for a quest" items, seasonal tonics and exchange items. Hell, I still have the Level 80 token that came with the original purchase, because I figured if I skipped to 80, I'd miss the Personal Story.

Is there a good rundown for discard/sell/keep somewhere? One thing I've seen in other games that I appreciate is when they say "these seasonal items are now obsolete and will be deleted/can be auto-sold for trifling sums".

Alternatively, should I just treat this character as a walking treasure chest, park him, and try to shared-slot things of actual value to a new character? Part of me says to fire up a revenant-- I always mean to try it, but I suspect now I'll be disappointed after spending my holiday playing too much Code Vein, where it was the term for "formally speaking not vampires, but, yeah... vampires."