I not sure I like the RX retaining system. It seems like it might easily work its way loose. Maybe add a Velcro strap around the RX and under the wood mounting deck passing between the existing holes.

Give us some additional model specific info, i.e., what model, engine and radio equipment is proposed.

Have you considered a pull-pull system?

How did you ascertain the rudder deflection would be 35 degrees?