The future may not be so bleak for you or anyone who likes bigger seats. In recent years, I've occasionally noticed narrowbody domestic F prices dropping out of the nonsensical realm and into a range where a rational human being might take a look at the fare and decide that it's worth buying the seat.

I would imagine this trend would continue - to the chagrin of would-be upgraders but potentially to the benefit of people who are willing to pay a fair amount for the extra space.

Every now and then, I even notice a long-haul J fare that isn't completely absurd. Long-haul J is still sold at much heftier corporate discounts than, say, a domestic Q-UP fare would be, so you don't see quite as many of these cheaper fares just querying Orbitz. But genuine discount biz fares (I'm not sure what exact fare bucket) do pop up from time to time.

Within coach, I imagine you already know which types fly with 18" seats vs. 17". IIRC, a lot (all?) of the Airbus types are 18", and within the RJ's I think the E170/175/190 are as well. I'm 6'4" 275 and for me getting the aisle seat on whatever type it is makes all the difference in the world. It's sometimes shoulder room even more than legroom that is a problem for me.