I mean, keep the same design for several years and only updating the CPU, GPU, etc. every few months like they have done with the fourth generation?
Eventually the iPad will have software to detect intentional/unintentional touches, the bezels will go away at that point. It'll be a display with a back. It will get thinner and lighter along the way and maybe more sizes will be introduced--but at that point in the design, what's to change?
So yeah, you're thinking is probably right on.
I think they are treating the iPad as a Mac. This is probably why they dropped the number, i.e. just iPad, not iPad 3 or iPad 4.
But let's be realistic, how many times can they keep updating it externally? It's a thin tablet with a big screen and a single button. I'm all for it being thinner and lighter, but I believe you hit a point in terms of thinness and lightness that is a sweet spot. Whether the iPad is there now or not is a matter of opinion I suppose.