Well, I mean, I don't think he wanted anyone to be Batman specifically or literally. Indeed, he wanted Batman to be unnecessary; he wanted Dent to be the shining figure who made Batman obsolete.
Thing is, Bruce Wayne could have been that figure -- and that's touched upon briefly in a couple places but not explored nearly as much as I'd have liked.
Something I think TAS did really well was depict him helping people as both Batman AND Bruce Wayne. He volunteers in a soup kitchen as Bruce. As Bruce, he hires a small-time thug that he just got through roughing up as Batman. There's a balance there that's forgotten far too often. (Even in Batman Beyond. I've said before that I love Old Bruce, but I really do think he's at odds with the more balanced, healthy characterization in TAS.)
And in the end, he certainly realizes the importance of leaving a legacy -- again, and this is important, as both Bruce AND as Batman -- and leaving the Batcave to Blake certainly indicates that he believes there may be a need for someone LIKE Batman at some point in the future.
But you know, we never do see Blake put on the cowl. For all we know, he could wear a domino mask and replace the bat-symbol on the chest with a blue V.
While it's implied that Blake becomes a new Batman, I don't think it's an accident that we don't see him in costume. (Any more than, say, the ambiguous final shot in Inception is an accident.)
Certainly there's the ol' "It's not who I am on the inside that's important, it's my actions that define me" -- but of course it bears noting that that line was deeply ironic given that he used it to REVEAL who he was on the inside. At best Nolan is giving us a mixed damn signal with that statement.
Which I'm kinda okay with, really. I like Dick as Nightwing and his own man; I also liked him as Batman and still clearly a completely different person than his predecessor. (I love the bit where Gordon turns around and is surprised to find him still there.) I DO think that, to some extent, the point of Batman Inc is that anybody can be Batman, but at the same time every Batman is different.
Hell, put it like that and I start to feel better about the "nobody can actually be Batman except Bruce" edict -- because each member of the Bat-family is just as much Batman as he is, no matter the color of the tights stupid-looking V-necked armor.