I absolutely think paragons are good for the game...they need some tweaks/balances, but this is the direction the game should be going in.
Right now, only casters have mid/late level abilities that are really cool/fun/different with ritual casting and high magic. Rogues and fighters have a whole lot of nothing...maybe more damage or more dodges, but that's nothing compared ot being able to cast a ritual or use high magic.
Not only that, but paragons add something that the game needs more of: Flavor. With paragons, two level 20 fighters could be completely different. They are basically prestige classes from D&D...and while those classes may not be the 100% optimal choice, they add a whole heck of a lot of flavor to the game. And that, in my mind at least, is more fun/exciting.
Now that paragons have been revealed? I don't think I'd be happy with them NOT being in the game. Even if you gave fighters and rogues some capstone ability...it's not enough. Paragons are likely my most favorite change of 2.0, just because of the amount of flavor it will add to each character and class.