Lets start with the landing gear. It does serve a purpose being positioned the way it is. It is form and function of the airframe. It handles great with the configuration as per spec. I would install it as perscribed. Secondly, if i can recall the pushrods are fairly close together after the final assembly. There is very little room for any change unless you decide to mount the servos in the tail section which is a whole new area of discussion. You will have to add weight in the tail later fo CG purposes. Last, I would use epoxy to cover the firewall for fuel protection. That should be done regardless in almost all cases where it is not done.