You may have issues with fabric stretch on the bias at your corners. What may happen is that the fabric stretches so much more on the bias ( which your ridgelines to the corner will be) that the centers of the sides will be well up off the ground before the corners come taut. If you don't mind them being up in the air, and you have enough range of adjustability with your pole to handle the stretch, then it may be okay, but it also may be a challenge to keep it taut thoughout the night if the fabric continues to stretch, as you not only have to keep jacking the pole up, but also loosening the guylines at the midpoints. I had one of the early chouinard megamids back in the early 80's, made from a light PU coated nylon which had too much stretch on the bias, and it had this problem - when the pole was maxed out the thing would keep stretching and so you couldn't get it tight, and if you jacked up the pole with a rock or something the mid-points of the sides were like a foot off the ground. They replaced it under warranty with one made from a heavier (1.9 oz) coated nylon, which they switched to, as mine was obviously not the only one with issues.
I'd go with a cutting layout that uses a little more fabric but keeps the stretch more equal on the lines of stress.
As for the heaxagonal shape and setting it up. I have an MSR twin peak which has a fairly similar floor plan ( thought it has two poles instead of one), and I'v e found it pretty easy to set up - I treat it as a rectangle at first, pgetting one end staked down and then the other, not too tight lengthwise, then the poles go in, then I do the mid-side stakes, pullng it tight, then I go back in and jack the poles up a bit (I'm using adjustable ski poles since this is my backcountry ski shelter) to get it nice and tight. Pretty easy, there's nevre any worries about how far out the middle points go, it's sort of automatic.