Every one had the same dungeons at launch, it's irrelevant, it's what you do after launch that matters. And I liked hard mode mixing things up honestly. It's about getting dungeons rotated through Expert faster so you're having a dungeon in there for 6+ months.
They don't take as much dev time as a full done, i don't really see a reason they shouldn't do them.
And just so it's straight here, I'm also annoyed they've cut back on WoW dungeons over the years.