Unlimited vertical is not the benchmark for F3A flying. With the Hacker verticals are also unlimited.

Now try to fly a looping in 20kts winds and try to keep a constant speed. Start downind at the bottomside of the looping. You'll see that you lack power in the last 45 degrees. It will make it, but not with constant speed.

A 16x12 is a bad prop for this plane, in my opninion. It's a small prop and it will make the acceleration problem bigger.

I'm flying a 18x10 prop on the Hacker. If it existed, I would be flying 18x10 Wide, for extra braking effect.

The acceleration might be solved with a good ESC with a good brake. The Master Basic OPTO 90 sebart includes standard, has worthless brake settings. The Spin 99 might improve this.