Dr-ji, you made a post! 😲
I basically agree with everything you said. Khushi's character is what appealed to me in the beginning too; I liked her from the get-go and never really looked back, despite the wardrobe atrocities and sometimes nonsensical antics. ASR, however, took some warming up to. I'm not sure if it was bad acting, audio-dubbing or a combination of a few things, but neither the actor nor the character impressed me until I saw his interaction with Anjali, which finally seemed to give him some depth beyond the woodenness of being a khadoos LG. (I actually rolled my eyes when they did that 'grand' helicopter entry for ASR...and it was a bit of a let-down when he first spoke and all I heard was a quiet voice/not the deep commanding one I was expecting...)
I've watched a lot of tv in my life and it always gets me that even when I passively watch IPK, I can't help but notice the sparks flying and the obvious effect it has on me as well. Granted, any decent actor can portray well-conceived characters/material, but you can't take away the individual and unique touches each person brings to their role. Arnav-Khushi's jodi/appeal was because of the talent of many people, most apparently the actors along with the writers, directors, producers, etc. Breathing life into the characters and the story was no small feat and they all deserve their due for creating such memorable personas and making IPK a success.