Professionally, Jupiter in Aries tends to come into its own where the pay is, in effect, for the ability to go in first. That covers one's own venture in a new niche, selling expensive and non-standard products, the uniformed professions, high-performance sport, crisis management, expedition work, front-line journalism. Anywhere you have to decide fast and not be frightened that half the decisions will turn out wrong.
Salaried work tends to sit badly with these people, especially under a cautious manager with long approval chains. Budgets and regulations read as a brake, and the person either leaves or quietly rebuilds the role around themselves. It's fairly common for them to be running their own thing by thirty — small, perhaps, but theirs.
I'd say the main career risk here isn't laziness or fear, it's scatter. Ten directions opened, not one carried through to a mature product. Recognition lands at the moment of the leap and feels like a finished victory, when in fact it's only the start of the real work. That's why a big, mature career for this Jupiter usually gets built after the first serious failure — it's after that, in my experience, that the person learns not only to begin but to close the loop.
Roles where your scale shows up at once tend to fit well: founder, producer, project lead, coach, mentor to newcomers. Mid-tier positions with long approval cycles tend to fit badly. If a career forces you into one of those for a while, keep a separate personal project nearby to take the fire. Without it, this Jupiter tends to start guttering and snapping at the people closest to it.