In #13 you say:
“…With adhimokkha as a condition, (Ariya) bhava arises. Note that an Ariya bhava arises via ELIMINATING a uppatti bhava. For example, one is “born” an Anāgāmi by eliminating the possibility of rebirths in the 11 realms of kāma loka.”
This means kusala kamma really removes kamma seeds, which is wrong! Uppatti bhava is like kammabhava a “stored abhisankhara” or a kamma energy. But kusala kamma cannot eliminate such energies. As you said Angulimala still had enough kamma seeds “on store” when he became an Arahant. So the sentence in #13 is confusing.
Can you write that kusala mula PS has no kammic consequences and just reduces the ability to operate the akusala mula PS? Thus “(Ariya)bhava” in kusala mula PS means just the “registration of nana/panna in the mind/namaloka” (sanna-, vedana-, sankhara-, vinnanakhandha). With that “knowledge” the mind will not grasp any bad bhava at cuti moment and increasingly no other bhava at all.