Lets look at consistancy.

Some Rep is painful to grind (HH/Thrall).

Other Rep is easier to grind, but pays off in small chunks (Aldor/Scryer).

Some Rep give good gear. Other rep is pretty meaningless or gives a single worthwhile item (Aldor shoulder enchant, Shat'tar head enchant).

Some rep is required for you profession (Old Mithril order, All rep for enchanting (which SUCKS!).

What you call 'dumbing down', I call giving more choices. My shammy needed Shadow Labs for rep (and Kara key). It took me 4 WEEKS of LFG to finally get a group that wanted to run SL. My guildies were SICK TO DEATH of SL grinds and couldn't be bothered.

I personally hate Shattered Halls. But I am an enchanter and need Thrall rep. So, if there was another way to GET Thrall rep, I am all over that.

What you call 'less fun', I call flexibility in how to achieve my in game goals. In real life, there are usually more than one way to do things. I think that the designers are working away from the 'one path, lead you by the nose' to the more flexible, here is the goal, here are multiple ways to achieve that goal, choose which is most fun to you.

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