Went for a lap with a mate in his RV last week, his pre take off included no turn back below 1000agl,,,,,,,I personally have the same decision height,,,,,and his 23000 hours flying everything but the box they came in makes me feel good about having the same attitude.
I'm not sure of the figure but I've heard it said that you'll lose a percentage of your skill in an emergency ,,,,very hard to factor that into the degrees, feet and angle equations,,,,,simple is better.
My first instructor taught turn backs at 500agl,,,,,,,I count him as a f**kwit in my aviation journey,,,,my next instructor taught 30 degrees either side of the nose on climb and no thought of turning back till the downwind turn( he is a much better instructor ), it's possible to make it below that but the stakes are high if you get it " just a little wrong"
Matty