Your idea about beeminding each acquisition from 0% to 100% reminds me of this idea, which I think you can do without beeminding each acquisition separately:
(that would be nice to turn that into a blog post, come to think of it. #blogideas)
And as for your question about retroratchet: that’s what you use to get rid of extra safety buffer. To add more safety buffer you can use the “take a break” feature to add an additional 50some days of safety buffer. (Sorry that’s confusing – we’re working on that. And thanks for asking about it. That helps us!)