As I am based in Medan, I think you just underestimated if you said not enough high paying passengers based there. Medan market is growing for both visitors and traveller going out. With only 3x per week on A320, the risk is much lower compared to the cities you mentioned which definitely requires widebody with bloodbath competition. For Medan based travellers the option available for international travel is only via KUL or SIN. So HKG is definitely a great bonus. 3x weekly on A320 will work just fine. Most of the international premium traffic only goes to MI/SQ with MH also get a little slice of the cake as well. So I believe KA/CX will do great especially with CX reputation in Medan is very positive.