What classes see the biggest improvement with small investment?

[Jimjam]

You can get silver chitin hand wraps and a wu’s quivering staff for 2k. Fill out with looted cloth then mesh armour and pick up some cheap magic shoes then hp rings as you level up.

If you have a character that can port you could probably do some of the sol ro quests on that toon to get some nice caster twink items.