How much scale details are you willing to sacrifice inorder to increase crawling performance? Are you willing to completely remove the flares and butcher the fenders for more tire clearance?
Personally, I wouldn't remove the bumpers nor the side rails. I think it makes the vehicle looks real and cool. On my Redcat Gen8, I've added a roof rack loaded with equipment, even though I know it will make the vehicle top heavy. But, I love how this look and I'm willing to sacrifice quite a bit of performance for it. This vehicle is more about scale and realism. If I had wanted an ultimate crawling vehicle, I would have replaced the tall, heavy Scout body with a low, lightweight body and add no other decorative scale accessories.