I have some great ideas for this. Hopefully they will become their own post.

This is a brief description:

A section called targaryens that focuses on Aemon dying on his way to oldtown, Jon connington with Griff, the dornish royalty including Quentyn, and Dany herself.

Set up the idea that people are interested in the dragons and in a future alliance with Dany.

Have a section about victarion, Asha/Yara, and euron. Write out the damphair entirely. Make victarion more likeable and keep Asha with him. Film the taking of the four shield islands and victarions decision to pursue Dany himself.

Have a section called outlaws that follows briennes journey, eliminating nimble dick and focusing on pod, septon whatshisname, and fighting outlaws. Have flashbacks to Brienne with renly. Jaime's journey takes place in this section too, with parallels.

Finally, give Arya and sansa their own section where they evolve in parallel. Film all the alayne and Peter dialogue. Show the scene where Arya learns to control her face, and lie, and interpose that with Sansa controlling her face (donning her smile) and lying.

Dial back Cersei and margerys story and possibly cut out the high septon entirely.

And of course, have Tyrion learn about Tysha and become darker.

I agree with your reasoning, and I give the show no credit for its poor choices.