In general critical care is going to be more emergency care in life threatening situations and IM loves both long term chronic illnesses and complex diseases. But that doesn’t mean an internist couldn’t or wouldn’t treat the same patients. I mean, it really depends on where you work and who else/what other specialties ar available. I’ve worked at places where there is no Crit Care and ER only works 5pm-7am; every morning IM takes over almost all inpatients that aren’t very clearly neuro or surgical. I’ve also worked places where there are a couple full time ER doctors that may keep some inpatients and IM may not take your parvo puppies, etc. And I’ve worked at huge tertiary care places where there’s a very distinct delineation about what each service is “willing” to take. Outlook for all specialties right now is excellent; there’s insane demand. Will it be the same in 3 years when people starting residency finish? Or in 7 years when current vet students finish? It’s anyones guess. The field is considered fairly recessionproof so I don’t personally see demand getting too crazy low (a slowdown might make things more managablw tbh) but it’s anyones guess what’ll happen in the future. I’d recommend you shadow in different specialty hospitals (or at minimum your schools clinic) to get a feel for what each service sees. But ymmv because vet schools aren’t necessarily real life either.