Well this is a first, an Experienced Points that I disagree with. Not entirely, but on some points.
I found my first play through of WoW to be one of the most enjoyable gaming experiences I have ever had. But I think that was to do with the reason I was playing it. I was taking the experience as it came, enjoying earning the right to explore all the new areas, watching my character slowly become more powerful. I wasn't focusing on an end point, on getting to a destination, because quite frankly I didn't know what came at the end. I was a true newb. When I got to the level cap I felt like I had really completed a journey. And what do you know, at the end of my epic journey I found there was almost a whole new game to enjoy.
On my second character though, I would agree with you completely. It was hard going, because all of the surprise was gone. I had already explored all of the fantastic scenery, completed all the amusing and fun quests before. I had been there and done that. Recently though, blizzard have added some stuff to the game to make it much easier to level an alt. There is experience increasing gear that you buy on your level 80 and send to your alt, and mounts at lower levels. (Yeah I know that one applies to first-timers as well, but seriously, who cares? All mounts do is reduce traveling time. They don't make it any easier to level, just faster.) I'm just gutted that that stuff only came out when I was really close to the level cap. Pfft.
I'll agree that blizzard do make you work too hard for your rewards. At some points, especially on alts, it does become a complete fucking chore. The only things that stopped me from quitting at those points were guild mates and friends.
I'd be apprehensive about playing a game that throws the rewards at you thick and fast from the beginning. I haven't played CO, but I'd be worried that the later levels became boring, as you had already been given everything they had to offer. Is this the case, or do they ration the new content right up 'till the max level?
Jesus this post has gotten pretty long, probably won't get a response. Ah well, thought I'd give my two cents.
NOTE - Recently I've gotten really bored with end-game WoW, but that's more to do with my laptop not being good enough to hold up in raids/instances than lack of content.