GaRCfield....
There are less painfull ways to get started with an aerobatic plane. You should be able to land a well designed "2nd plane" on the strip or in the weeds, power on or dead stick, without any worries.
This scenario is par for the course with the conventional wisdom, conventional advice. What is happening here is what keeps those guys behind the cash registers happy. It's like a broken record.
A 3 pound, 600 square inch 3D profile plane [with the landing gear left off intially and the controls set up conservatively] will fly circles around any of your typically recommended "aerobatic trainers", land at your feet, forgive any mistakes [except for running out of fuel in a hover 10 feet AGL], be extremely easy to fly and will receive much less damage [less inertia] if things happen to go really wrong. I mention using no gear because hand launches are no sweat and you can land in the rough if you like.
I think the typically recommended 2nd planes should be moved down to #3 or #4. There will always be time to learn all the other stuff that the conventionally wise-ones want you to learn [all at once] with this "2nd plane" that you are repairing now.
It sounds like you are already at a stage where you can fly a plane that will go where you point it, but what you still need is a plane that is much more forgiving of mistakes. This is why I think a quality .25 to .40 sized profile is the best "2nd" plane if set up intelligently [low throws and built light].