Hi, I'm a mid-core player who used to raid Savage. I want harder stuff. I don't have the time for Savage any more but more middling content like the 24 man raids would be excellent. I'd be okay with going down to one dungeon every patch if we could get more stuff like that, honestly.
As for dev capability, they get there eventually. I'd rather see them try new things, fail, and improve than keep things as they are. I'm even willing to give players the benefit of the doubt and say that most of us can handle a bit more difficulty than what we see currently. I'm not asking for all dungeons to become savage, but they can nudge us to do a little more than space out as we push the shiny buttons.