Your definition of 'safer': Is it about financial security, flexibility, or control over decision-making?
Your risk tolerance: Be honest about how much uncertainty you can handle, both financially and emotionally.
Support system: Do you have people who can offer support (even practical help) on either path?
Before you decide to go full-time: Analyze your current startup's potential, your financial runway, and have a fallback plan for the worst-case scenario.
Before you decide to go part-time: Be realistic about limitations as a part-time entrepreneur.