I think we need a four legged bot for frontiers, just to spice up the variety. It could be like the Weyland, with two heavy weapons on the sides, or like the Rayker, with two light slots and one heavy. I would think that Quadruped robots would be slow, but with high weight and fuel capacity.
#Spider bot?
short wigeon
lapis hearth
A spider bot is in development. As of when and who, that is unknown