If I remember right, Keith Baker has/had a website where he would write 'his' Eberron, which I thought was interesting to see a designer's version of their setting, done without committee.
One article he had that I found very interesting was when he got into the concept of reskinning, which maybe some players weren't familiar with, and as an example, he reskinned a barbarian into a Brelish supersoldier, if I remember right, who instead of being a raging beast, their powers and rage came from alchemical experiments that had been done to them
If you really want to do a deep dive into the Eberron setting, Keith Baker's blog is a must-read. He adds a ton to the pre-existing lore and you can also take or leave what you want

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.