If a theory purports to explain everything, then it is likely not explaining much at all.

I don't see any Stoic practice as problematic or risky, but I would advise to engage in extreme versions of the negative visualization exercise only if you are an advanced practitioner. The negative visualization is a meditation during which you visualize, slowly and deliberately, something bad or discomforting happening to you.

Death itself is a natural occurrence, it is unavoidable, and the Stoics thought that part of philosophical practice is to get comfortable with the unavoidable, learning to face it with courage.

The downside of skepticism: it can easily turn into an arrogant position of a priori rejection of any new phenomenon or idea, a position that is as lacking in critical thinking as the one of the true believer, and that simply does not help either science or the public at large.

The Stoic discipline of action, which is connected to the virtue of justice, says that we ought to treat others fairly and we should engage in social and political activity. This is further supported by the Stoic idea of cosmopolitanism, and by the famous "circles of concern" identified by Hierocles, who counseled that we should refer to other people as brothers and sisters, to constantly remind ourselves that we are members of the same human family.

I believe Stoicism can help anyone who takes it seriously and begins to practice it. It will help them flourish because it will provide them with a compass for navigating life, a general, flexible, framework to set priorities, and a set of techniques to achieve serenity and equanimity.

We still live in a world of such gross injustice and inequality, that only privileged people like ourselves can afford to think of eros and art as top concerns in life. They are important, for sure, but I think it's high time to shift priorities around, away from selfish indulgence, and toward more concern for the wellbeing of so many others who suffer atrocities, injustice, and famine, all over the planet.