About the first point, I still disagree with the parent comment. The standard 0,5mg/kg ketamine is given under 40 minutes. I've seen two patients receive it. The room was dimly lit, silent and peaceful, as to not induce or exacerbate any possible dissociative or hallucinative side effects. The patients didn't report any side effects at first and later reported a little sedation. I wouldn't be a able to tell with certainty if they had received a placebo or ketamine, and certainly not within minutes.
Source: psychiatrist in training
Edit: I still think we need hard data about anti-suicide effect and not just surrogate markers. Variability in suicidal ideation is suggested to be a predictor of suicide attempts [1]. If ketamine first gets someone better and later on they relapse, they could, in theory, be at increased risk for suicide. More long term data is also needed about it's long term effects. Note that I do think it's a good thing that ketamine is becoming more available! I will continue to suggest it for e.g. patients with treatment resistant and severe depression.
[1] https://www.sciencedirect.com/science/article/abs/pii/S01650...