Try to eliminate as much slop as you can in the elevator linkage as designed. You can route the antenna happily through the other boom, but I'd make an internal tunnel if you can, not cut through the skin as recommended for the elevator pushrod. Never liked that.
This is not a terribly high performance glider, but it does glide well in a sport R/G kind of way. Certainly a vast improvement over the Astro Blaster, though it uses the same wing. If I had the time and inclination I'd mess around with the airfoil but I don't so I haven't.
The Strato Blaster lends itself well to CHAD staging due to the loacation of the motor mount relative to the CG. Flown many times on D12-0 to D12 or E15, now of course you'd use the E9.
It's not light, so eliminate all the unnecessary weight you can as you go. Small battery pack, small receiver, small servos but not too light.
Mike D.