My 44 still isn't here, but just looking at my wife's 40mm it's already better than my 42mm. I can't even imagine what the 44mm is going to be like in person. Part of me wants to go to a store to look at it, but part of me just wants to wait and experience it on my wrist for the first time. My #1 complaint with my Series 0 over the years has been speed, but my #2 complaint is interaction/usability, and this looks to go a long way towards solving that.
That being said, my wrist is big enough that if they wanted to redesign in a few more years and push the display even more to the absolute edge and introduce a third "max" version at 48mm, I would be all over that. I love the idea of a more fully functional wrist computer. I think the really long-term goal for Apple (decades) is an Apple Watch-like wearable that transmits a display signal wirelessly to regular looking glasses or even contact lenses powered by the body's natural electric field to produce augmented reality overlays and information right in your line of sight. Just not sure how they would do the contact lens thing without a camera/depth sensor array somewhere on your face, but to be honest the contact thing is already super advanced and in the far future so who knows. But something like that could potentially kill the iPhone if anything in your field of vision could become a multitouch display.