1] Hey, the new Migrate Process to Flow utility works!
It still has a list of Things It Won’t Do, but at least at first blush, it took one hairy legacy Process and converted it to Flow (apparently) correctly. hm!
2] Hell yah, relative values have come to Reporting! Check it out:

Of course the documentation says it’s only available in Lightning, but who ever totally trusted the documentation.
Further updates as events warrant!