I don't think we will be getting QuadVee versions of Scorpion and Goliath, those two are way too bulky plus RecGuides already hinted that they are due for Omni treatment
The Goliath is too big, but there are QuadVees heavier than the Scorpion.
I believe that current Design rules limit QuadVees to under the Assault weight (or just barely in the Assault weight class).
Still, that's getting in to Fan Design territory.
Would like to see models of more current QuadVees than the Arion, though.
honestly, I doubt it, the main value of tanks over mechs is cost. quadvees kinda eliminiate that.
True, however, they are more survivable than tanks, and have some fun shenanigans they can pull, as well as being more easily transportable, with the lighter ones able to use Light Vehicle Bays.
And I wouldn't limit them to just Davion and Steiner. There isn't a House, Great or Periphery, that wouldn't like to try them out. The capacity to develop them is a different story. Most of the ones that are capable, just aren't close enough or have any experience with them.