You can have tip stall margin, both upright and inverted, at the expense of roll rate by using little or no taper in the planform.

You can have speed by using a thin airfoil, small crossection fuselage, retracts, a well cowled engine and, a long tail moment arm with small tail surfaces. The results will look much like an electric “hot liner.”

To get the high lift coefficients out of a thin airfoil so that you can do high G maneuvers, you will need full span flapperons coupled to the elevator channel. The flapperons will help lower landing and takeoff speeds.

You will need a unicarbon spar that can take 30 or 40 G’s.

If you want to keep your speed up in the turns, you will need a high aspect ratio to limit induced drag. Unfortunately, this will also limit roll rate.

BTW, dynamic soarers have hit 170 MPH while flying tight circles. You might look to them for some spar design ideas.

You will need a prop with low enough pitch to take off but high enough pitch that it gives a high top speed. The wider the range of RPM the easier it will be to prop for the desired performance.

Finding the right compromise between the conflicting objectives is the challenge.