The Starks are the heart of the story
It’s been said before, yes, but a huge part that gives away or rather helps the audience feel what they should be feeling is the music.
Listen to the music when Jon gets proclaimed King in the North in 6x10:
One thing Ramin Djwadi(the composer) is known for doing for Game of Thrones is taking notes from two or more pieces from a house theme and combining them to make a new piece. For example, the piece that plays in the background as Jaime leaves Cersei, ‘No One Walks Away From Me’, has elements of ‘Rains of Castamere’ and ‘Light of the Seven’. It makes sense since Rains is House Lannister’s theme song, and LotS was the theme that plays when Cersei pulls off blowing up the sept in 6x10.
In ‘Winter Has Come’(the music that plays when Jon is proclaimed KiTN) however, it has elements of House Stark’s theme - from ‘The North Remembers’ to other House Stark themes that use the same piece, just played in different octaves/variations - so from that it’s already clear WHC is a Stark theme. But more importantly, towards the end, it has elements of Game of Throne’s main theme.
Did you catch it? At the very end, is the theme song of GoT. The iconic opening song. Which house theme has it finally and so clearly been tied to? House Stark.
Yes, in season 1, the season finale ends with the theme song after D*enerys births her dragons but now that we’re in season 7 and there’s been a shift in her persona and arc, it’s difficult to find any trace of the main theme playing in her Targaryen pieces. She’s beginning to embrace more and more of her Targaryen roots in costume too, and the music reflects that. Go ahead and listen to her music - it sounds fitting for a conquerer. She no longer has moments that allow for the main theme to sneak in and help reflect what we should take in.
The story started with the Starks and it will wrap up with them, trust in that.