Your first recipe is pretty similar to the one I use although I use turkey red oil for my oil and I also have salt and cornstarch in mine. I use powdered surfactant at 8-10% of my total recipe.
General rule of thumb is 2 bicarbonate to 1 citric, so the first recipe looks better balanced, the second not so much.
I am not super experienced but I find that the molding is a pretty delicate balance - too much in the mold and they break in half. Too little and they crumble. Also, I unmold mine almost right away (I use a meatballer). If it breaks, I throw it back in the mixture and try again.
What are your cupcake molds made of? rigid plastic? silicone? Are they single or multi-cavity? What's your technique for extracting them?