I got my thief to level 80 before Nov. 15 and was always able to equip him with green or blue armor and weapons that were within ~5 levels of his current level, just from mob drops while levelling. I started trying to level a guardian some time during mid November and found that I had a very hard time staying well-equipped after level 20, I had to take up armorsmithing and weaponsmithing, early on just to help fill in the gap. As of right now my guardian still isn’t level 80.
I have not noticed any significant difference in dye drop rates while playing on both my thief and guardian, or a difference in ecto salvage rates. However, recently my collectible items have actually been hitting the 250 mark in the collectibles tab, while playing on my guardian, and I’ve had to TP spare crafting resources. That never happened while I was playing on my thief, which barely hit 80 or so in any of the collectibles.