The 4/40 hardware is plenty strong by itself, the carbon fiber rods add extra weight you don't want on this plane particularly at the rear. I did use the stock hardware but I don't recommended it

You want to get as much leverage advantage over the control surface as possible with the control horns. This means using a hole as far out from the surface as possible . For 3D throws this usually means you need to use extra long servo arms. I used the stock control horns and the very last hole at the tip. If the first hole is used you are very likely to experience flutter

What engine are you planning to use?

I would reinforce the wing hold down mount in the fuse .It looks like a design destined for trouble and someone has recently experienced a failure