They were overpowered as hell, but that shouldn’t be what makes the class special. There was talk originally of them being based off an exisiting character, which sounded cool but I can see why they nixxed it.
The starting area was cool as well and the mount etc. Rune weapons are varied sure, but I still think that they could have been better implemented as something unique to them. Just being able to enchant any weapon from the runeforge didn’t really satisfy it for me. At least Legion gave you the artifact weapons, so that’s cool.
I might be alone on this, and that’s okay. I just felt like they could have been more iconic than they were. Remembering of course that they were implemented before transmogs and you could end up using just a generic looking weapon as soon as you left the starting area.