What do you value more? Every year flying a King Air is a year off the end of your airline career. A 44 yr old hired today would retire around #1575. That’s 11% overall. About 5 yrs as a 777/787/330 CA in the junior bases. One to two yrs in the senior bases. Or you could stay as a n//b CA and retire around 14% in a senior base or 4% in a junior base.
The pay you’d forgo would be around $350,00 per year. So the King Air job would ‘cost’ you about $200-250K per year.