So if you argue against off chain mixing, you fail to note that your on chain depends on your off chain IP obfuscation, so your entire thesis of defense collapses in a house of cards.
The two are complementary. Even Bitcoin can be used with Tor, etc. But even if Tor, etc. are assumed to be totally bulletproof, that does not provide any protection against blochchain analysis.
Cryptonote can be viewed as Bitcoin with defense to blockchain analysis added. Other existing solutions attempt to do that with masternodes, network peers, etc. I think our approach that relies on cryptography rather than shuffling data around the Internet between various nodes is easier to analyze and therefore more likely to actually deliver what it promises. (Though, as always, no 100% guarantees in life.)
Other approaches that are distinct from both Cryptonote and current off-chain mixers may also be useful, or even potentially (much) better, but Cryptonote is here now. That is worth a lot and even in its current rough (but rapidly improving) form, improves greatly on Bitcoin with respect to privacy.
On chain just adds vulnerability
Okay, now it is pretty clear that you are "selling" your approach. It may not be what you intend, but that's how it is coming off.
Go build it. A demo is worth 1000 posts.