With the shocks you can either cut down the springs or take off the height adjusters. I ran my Durga indoors usually with the ride height adjusters taken off so the car sat low enough. Outdoors I don't think I'd usually want to go that low tbh.
The steering shouldn't have any real noticable bump steer no, don't have a durga anymore but I'd recheck your manual to make sure the steering is built correctly maybe?
No options for the rear toe afaik - unless Tamiya make some rear hubs with different degrees? I know they had prototypes but not sure if they are released or not. I think it's 3 degrees but I never worry about toe angles, there's so much more interesting stuff to setup
