Let's just get into it straight away. "Meaningful" content is extremely subjective. For some people transmog is meaningful. For other people gold farming is meaningful. It completely depends on who you are. So the idea that Blizzard can tell us "this is a meaningful choice" is absolutely insane. Because it only holds meaning if it has meaning for the specific person.
In the latest Preach Interview Ion said two things concerning the Conduit Energy that really annoys me:
1) "They wanted to avoid another system where you swap to Conduits on every boss."
Why? Why is it a problem if a few players wants to swap Conduits for every boss? It's a part of class customization. And most players wont do it anyway just like most players don't even change talents between bosses. Why do you have to make these unnecessarily restrictive rules just because a few players are going to swap conduits on every boss. Also, it's not like the conduits have any complexity. It's just another passive talent row.
2) "They want to avoid situations where people are swapping every day, but every week, that's something they want to accommodate."
Again, WHY?! Why is it a problem if people swap conduits every day? You cannot dictate this to be a "meaningful choice" just because you want it to be. Most people pick the strongest spec and the strongest conduits for that spec anyway. That's already not meaningful for us. My transmog is a more meaningful choice to me than my conduits. The only thing these restrictions achieve is stopping people from having fun with off specs.