This is an excellent post, both the news of the upcoming lit mag, and also the straight talk about craft and what readers want. Yes to an early hook, yes to white space, yes to respecting the reader and "trimming the fat."
Yesterday I put on an audiobook to listen to while I puttered around the house. It was a fantasy tome published in the 90's, and I maybe listened to 30 minutes of it. I'm pretty sure if the author tried to get it published in today's market, it wouldn't fly, because omg were there unnecessary words. Loads of them. Evolution is a thing. Innovation, as well. And I find it so interesting to watch how publishing changes, even year to year.
All that said, the advice that sticks with me as a writer is "write the story of your heart." Do it with everything you know, honing your craft as much as possible, but write the story that calls to you rather than trying to write for a market that might change before you get a chance to publish.
I'm looking forward to reading the SHP lit mag, and hopefully writing for it, too!