Not posting this as an issue yet as I want to check with other users to see what they think of it first.
My own observations lead me to believe that the walrus understeers far too much, especially considering it has 4 wheel steering. This does seem to get worse as you put heavier armor on it but that makes sense. The issue is not that heavier armor affects handling, but rather the base level of grip being too low, and perhaps the amount the armor affects the handling. I think it could stand to be toned down a little.
Also I think the poor grip may be a contributing factor to why the pathfinding works so poorly. Having ordered a walrus to drive somewhere and then follow it with another walrus, I watched how it turned the wheels and where it actually went. It was sliding all over the place and often struggled to turn the way it meant to go.
I want to hear how the rest of you guys are experiencing the walrus handling.