It's a neat timeline, but I don't agree that The First Avenger should be watched first. The main story is framed by events taking place during the present, which lack context if you watch TFA first. Iron Man is the best introduction to the MCU, in my opinion. This is the viewing order I've put together for my own personal rewatching:
Movies
TV Shows
"One-Shots"
1. Iron Man
2. Iron Man 2
3. "A Funny Thing Happened on the Way to Thor's Hammer"
4. Thor
5. The Incredible Hulk
6. "The Consultant"
7. Captain America: The First Avenger
8. Agent Carter 1.01 - 1.08
9. The Avengers
10. "Item 47"
11. Iron Man 3
12. Agents of S.H.I.E.L.D. 1.01 - 1.07
13. Thor: The Dark World
14. Agents of S.H.I.E.L.D. 1.08 - 1.11
15. "All Hail the King"
16. Agents of S.H.I.E.L.D. 1.12 - 1.16
17. Captain America: The Winter Soldier
18. Agents of S.H.I.E.L.D. 1.17 - 1.22
19: Guardians of the Galaxy
20. Daredevil 1.01 - 1.13
21. Agents of S.H.I.E.L.D. 2.01 - 2.19
22. Avengers: Age of Ultron
23. Agents of S.H.I.E.L.D. 2.20 - 2.22
While Iron Man 2, Incredible Hulk and Thor all take place within the same week, I placed Iron Man 2 first because it's a direct sequel to Iron Man 1, picking up six months after Stark revealed that he was Iron Man.
I put Thor after IM2 because Coulson leaves for New Mexico in IM2, and arrives there in Thor, so it would be awkward if we have a whole other movie in-between. And I put TIH third because it must take place after IM2, when Stark becomes a consultant for SHIELD--or the final scene must, anyway. But seeing Stark visit Ross and then jumping back in time for IM2 would be confusing.
And then I put The First Avenger as the last of the pre-Avengers movies primarily because it serves as a perfect setup, with its focus on the Tesseract. Also, it felt like Rogers hadn't been unfrozen for too long before he was put into action, so it makes sense to jump into Avengers immediately after TFA.
I don't include the Agent Carter One-Shot because the TV series covers much of the same ground, basically putting it out of continuity. I treat it like an unaired pilot. And I put All Hail the King in the middle of AoS season one mostly so that there would be some time in-between it and IM3, allowing Trevor Slattery time to build up his mystique in prison. I placed it between "The Magical Place" and "Seeds" because there was a clean break between storylines with those two episodes, so it wouldn't be as awkward as watching AHtK in the middle of a story arc.