caveat - I don't know rally other than thinking that it is cool, and too hard on equipment for me to participate.
From a driver perspective, there might be some rationale to keep it, if autox and rallyx are target activities. It does help with steering quickness. However I could see potential for fluid getting hot and other issues too.
From a car perspective - I would absolutely dump it. The pump is in a vulnerable position, and the whole system just adds un-needed weight to the wrong end of the car. The manual rack will be the lightest, but just removing the pump and lines and looping the lines at the rack will be the cheapest, and will retain the quicker ratio. If you are not constrained by rules, this would probably be the best route.
In my road racing application it was a no brainer to go to the manual rack.