There's no shortcut around the geography here: John Wayne Airport doesn't offer a single nonstop path to the Aegean, so business class from Orange County to Mykonos always involves at least one, often two, connections, and the routing you choose matters as much as the cabin itself. The most reliable structure I've found after years of booking this corridor is SNA to a European gateway, then onward via Athens on Aegean Airlines, since Mykonos itself only receives seasonal, mostly narrowbody service that rarely carries a true long-haul business product. British Airways via London Heathrow puts you in their Club Suite, with its direct-aisle access and sliding door, on the transatlantic leg, while Lufthansa routes through Frankfurt or Munich, where you may encounter the airline's newer Allegris business seating on select aircraft, though not yet fleet-wide. Total journey time hovers around 14 hours of flying, but with connections, plan on 18-22 hours door to door.
The insider move is booking the SNA-to-Athens segments to arrive with at least three hours before the short Aegean hop to Mykonos, since Athens International's connections between international arrivals and the domestic/Schengen gates can require a security recheck that catches first-timers off guard. Aegean's own business class on the Athens-Mykonos leg is a modest but pleasant regional product with blocked middle seats and proper catering, a nice palate cleanser after a long-haul flight. Shoulder season, particularly late April through May and September into October, is when this route rewards patience: island infrastructure is fully operational, Aegean adds frequency, and long-haul business fares from West Coast gateways into Athens or London soften noticeably compared to July and August peak.
Because pricing on this itinerary swings with both transatlantic fare sales and Aegean's seasonal capacity, I'd treat static searching as a losing game. Setting continuous fare alerts across BA, Lufthansa, and Aegean combinations is the only way to catch the windows when premium cabins dip.
