I’ve found that bone stock 5.9s don’t need anywhere near 36 degrees of total. In fact if you watch Richard Holdeners 5.9 testing on you tube he says his made best power around 27 degrees. I think I settled around 30 for mine. +-1 deg. They make peak torque around 3200 so I’d delay the all in till about that point. I like your 16 degrees initial and I’d build a curve with two stages. Bring in like 8 degrees pretty quickly with a light spring and use a little heavier one to add 6 or so more after peak torque.