Okay, another step forward. I tried doubling the borax and got a better result, but still not quite enough contrast. Then I doubled the hydroquinone (as well as the borax), and this test neg looks to be in the ballpark--possibly on the grainy side, but I'm mainly looking to use this with large format, so that's okay. With Arista.EDU 400 I've got good shadow detail and reasonable highlights at EI 1280, 20 min. at 86 deg. F. Next I'll try a little benzotriazole to see if I can keep down the base fog a little more.