Jim Hines posted yesterday about the Best Editor categories of the Hugo ballot. A friend asked who might've been on the Best Editor ballots if not for the Puppies slates; I wrote the following as a response, but figured I might as well promote it to a full post.
The Best Editor categories are among the ones where the nominees historically didn't tend to change much year-to-year, though there's been a lot more change the past few years than there used to be. (In particular, the Long Form list tends to change much more than the Short Form list.)
So one way to see some of the people who would've been likely to be on the ballot if not for the Puppies is look at the past few years' worth of nominees.
In particular, in Long Form, Liz Gorinsky is the only editor who's been on the ballot in all five of the past years. I'm not certain what she edited last year [post edited to add: she edited Ken Liu's English translation of Liu Cixin's novel The Three-Body Problem, which likely would've been plenty to put her on the ballot], but my guess is that when the nominating numbers are released (after the awards are given), she'll be high on the list. Other recurring nominees who might've been likely: Lou Anders (seven of the past eight years), Patrick Nielsen Hayden (six of the past eight), Ginjer Buchanan (six of the past eight), and Beth Meacham (three of the past eight).
In Short Form, it seems quite likely that four of the slots would've gone to Sheila Williams (nominated every year for the past nine years), Jonathan Strahan (every year for the past seven), John Joseph Adams (every year for the past four), and Neil Clarke (every year for the past three). The fifth slot might've been Gordon Van Gelder or Ellen Datlow. Or possibly someone else, but those seem likely.
Actually, Gordon seems especially likely, because in January he stepped down as editor of F&SF. But I'm guessing he'll still be eligible next year, 'cause I think he was editor for the first issue or two this year.
Another possibility: Trevor Quachri, editor of Analog, although he doesn't have the name recognition yet of his predecessor Stanley Schmidt.