I think very fluffy people don't always have the problems you think. It can be really varied.

Goal weight is hard. I have NEVER been thin. And at low weights I am still plus size. At 130-140 I started in plus sizes at my full height (5'5"). My main motivation for being normal BMI would be to fit in "normal" clothes but it's never been feasible so I just don't think about it. I know that losing weight is hard on my body, no matter what. I always get injured when I'm losing and going below 180 is the worst. My body just starts falling apart. So that's my low weight. 200 is my goal-ish. When I use to run, I ran better and faster at 230 than at 190. So I just go by how I feel, general fitness.