I want to travel to Shanghai with my family (2 adults, 1-five year old, 1 infant) in November 2024 (dates flexible mid October-midDecember, can be for 20+days).
Departure: LAX

I have points:
Amex MR 350,000
Chase. 160,000
United 135,000
Capital One 80,000

Class: Economy or Prem.Economy
Can do stopovers for 3-4 days in Taipei or Hong Kong. I know infant redemption is difficult. What is best airline to search for good redemptions for this? So far I see Cathay and Alaska, but I may need to call after to add the infant seat.
Bit new to airline award redemption. Thank you in advance.