I'm a huge fan of Extra Credits' helpful explorations of games. While I can't say for sure if the dev team watches it, I'm pretty sure choice and conflict, as explored in the EC episode, is something they think about constantly because it often creeps into comments and replies about certain systems.
For example, before release, Jay mentioned that the number of skills chosen was reduced to what it was because with even one more, "people could get pretty much everything they wanted". By reducing your options, you have to make some harder choices.
With the affixes we have, certain slots especially have almost a dozen especially valuable stats, and yet at best, we are going to get 6, maybe 7. Or on many Legendary items, there are a lot of special and interesting stats, but few of the "main rolls" might be left, so that you have a very hard choice to make. The Stone of Jordan is a prime example of this. You get a big helping for resources, damage against elites, an elemental damage boost, and a skill boost. But you can't get any defenses, primary stat, crit chance or damage. (Of course there are examples of Legendaries that fail to do this, like Vile Ward which mostly has the stats you want most that are available on shoulders)
I hear a lot of groans about proc coefficients, but they exist specifically to create choice conflict between different abilities, and balance them as legitimate choices.
And in the latest Dev Q&A, Wyatt mentions that creating conflict in choice between areas that might be more efficient for farming for particular reasons might be what determines the routes you prefer.
So, I find it surprising that you bring choice and conflict up as something that "needs to be applied" to areas where it is already strong. Like any system, there's always room for improvement, but as Extra Credits mentions when talking about playing like a designer "you have to dig down and try to get to the heart of why" you feel these principles aren't applied strongly enough. If you can manage that, I'm sure Blizz would be ecstatic to hear your thoughts.