Since I'm in the job market, I'll take a positive outlook. For years people have been saying the NCC market is becoming "saturated," I was even told this as a med student > 5 years ago. There may be some truth to it, but I think prospects are decent overall. Even though you have many divisions with full cohorts of attendings, you still have job openings when people leave for a better opportunity, cut back, or retire - same as any other field. Just from observing job listings and talking to people, I know several big academic places throughout my region have recently hired, It's just that you can't walk into any division you want and ask for a job anymore. 5 or 10 years ago it was easier to do that as even some highly academic places were still building their units from the ground up. Outside academics there are a lot of CSCs in larger community hospitals that are building/expanding NCC so I think those opportunities are decent as well.
I don't necessarily think salaries are less than pulm crit. Remember these numbers are for new fellowship grads - who knows how much salaries go up with time for veteran attendings. The drastic pay cut you take with academics holds true for any field. You can be a neurohospitalist in the community and make a lot more than NCC in the right scenario. You can do NM in the community and make more than an academic neurohospitalist, etc.
Competitiveness is on par with vascular. Neurology fellowships (with exception of endovascular and pain) are not particularly competitive overall. It's more dependent on you and where you're willing to move after 4 long years of residency. You don't need a ton of research for fellowship but your interviewers will still try and gauge your interest in the field, research is just one way. Stroke definitely doesn't make more than NCC, but again, its more dependent on region and academia than anything else.