I actually prefer not having characters gain all the features of two classes, but I agree that a) The multi-class feats need to be adjusted in cases where they don't grant access to paragon paths (like for the ranger), and b) Paragon multiclassing is weak, asking you to give up 3 paragon features in exchange for the opportunity to swap out an at-will.
I'd rather see the paragon multiclassing adusted to just give a relevant action point-based feature and the most important class feature not given by the multi-class feat. So, for clerics and paladins, that would be channel divinity, for wizards it would be the spellbook, for fighters it might be combat superiority, a choice of "presence" for the warlord, the ability to curse someone for the warlock, I would probably make hunter's quarry a paragon multi thing and let the warrior of the wild feat give one of the fighting styles, and likewise for rogues I might swap sneak attack to paragon-level and have the feat give a choice of rogue tactics.
