A great question and a tough one as you imply. I'd speculate that the answer includes:
1. Re-locate the island to be nearer the bigger and richer populations of London, all of southern England and western France
2. Implement a similar superior climate?
3. Create an economy with a comparable size and make-up to Jersey's - e.g. their very much larger Banking, Corporate Services, Insurance, Investment & Tourism sectors?
All quite challenging asks!