heres the new route -
Hong Kong - through various contryside town - Chengdu
Chengdu - Xi'an
Xi'an - Bejing
Bejing - Shanghai
That's an awful lot of countryside towns..
I'd say avoid Guangdong altogether, go to Guangxi, the karst peaks, can't really do without the daft Western tourists there (Yangshuo), but still, too good to miss, bike around (with a guide) then down Southwest, the anteroom of Vietnam, then, or maybe before that, why not Gui Zhou, the minority villages, the amicable Miao and Zhuang in their reservations, wohooo we all live in the halmonious society, have a thought for them, and for the rough, uncompromising Dong in the mountains, then lose yourself in Yunnan, (formerly) secret paradises like Yuan Yang, just next to Burma, up to Lijiang, Dali, dispensable Shangri La, the doors of Tibet, then finally find your way to Chengdu, then why not stop by any of the Dickensian towns - fancy Lin feng? - sheer eeriness, see some real Chinaland, only then up to Xian, fine, then all the way to the new centre of the World, the hordes of black Audis and pink Cayennes, give them a stern finger, I always do, scares them shitless, congratulations captain, you've made it, oh yeah and Shanghai, better city, better life bwah!
Quite a classic route, so feasible in 4 to 5 weeks...As for the rest, personally I'd avoid Anglosaxonia entirely (especially if you're a Brit....where's the challenge?)...why not pick one between Africa and Latin America instead?
And Venezuela is the toilet. (Sorry, Fabi. 
)
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Greatness, but I think all of S. America can be the toilet and MG is the rat that lives in your bathroom cupboard.
