Luna
I read your post and I see everything that caused me to leave the MO world I grew up in.
Now granted, everything I am about to say can apply to every Jew no matter what level he is at.
That said, rationalization seems to be more of a disease in the MO world than black hat.
In the yeshivish velt watching TV is something to be kept hidden because we recognize the inherent evil. So even when we are nichshal, we at least recognize the inherent wrong. My MO friends see it as having positive secular culture aspects.
When discussing meticulousness of halachos, those halachos they don’t want to keep are “chumros”
You even said “most halachos”! there is no such thing in orthodox Judaism as keeping “most halachos”! Its all or you arent orthodox!
Torah IM derech Eretz was never about going to theaters and culture. Thats hellinisim
As for a source (gavrah at work) try pachad yitzchok, maharal etc
The same goes for yaft elokim lyefes
There is no concept in Judaism for embracing goyish culture