Manual printer here but, for what it's worth, I rarely use anything but 70/90/70 and am very happy with the stuff. A little straight 70 here and there, particularly on the larger, 16" squeegees as it seems to be a bit more forgiving for wide prints. We have one little 10" guy with 60/90/60 and it can lay the ink down but is a bit too floppy for a push stroke and thick bodied ink. Got rid of all the 60s when I switched to a push stroke years ago.
What about a 55/100/55 ? Or, what I'm getting at is some kind of super soft outer blade with the middle of the samich being really stiff to support the blade throughout the whole print stroke.
