The red line path is only good for a handful of things:
Gets you to the Temple of Kynareth marginally faster if you're handing in a quest (e.g., the delivery for Idgrod the Younger in Morthal, or the one where you murder a hagraven outside of Helgen for her magic knife)
If you are befriending Lars Battle-Born so you can ransack his house to find proof that the Thalmor are holding that one Grey-Mane dude captive
If you need to go play Elder Scrolls: Mortician's Assistant up in the Hall of the Dead
If you have ADHD and get distracted by the shops and you need to hang on to every last septim until you've bought that motherfucking homestead and oh god there's dragon's tongue and soooo much tundra cotton over there but oh fuck my carry weight is at 299/300 because I refuse to level up and dump points in stamina just yet because my gear sucks and I can't afford upgrades yet and no no no I will not pick the flowers right now I need safe storage somewhere first so I'd better run past the bougie fuck with the cow in the middle of the damn city; why is there a cow here? THEY DIDN'T THINK OF THE SMELL
The red line path is only good for a handful of things:
That's really about all I can come up with.