Where Should You register your first startup company?

A friend of mine just started working on his idea in Beijing, which really made me think extra hard... where shall one register and start his/her very first startup company?
As lots of media has published, Singapore ranked #1 the easiest place in Asia to start a company. However, from my experience, it's darn simple for Singaporean citizens and Permanent Residents. I've not figured out how to register a sole foreign owned company in Singapore yet. Maybe, one has to have a local partner.

Another destination might be Hong Kong, as more and more Google Ads pop up on my Blog suggesting that Hong Kong has very good policies for starting companies... Yes, I guess it is. When i was attending some legal structures of a company in Beijing and else where, Hong Kong always poped out as one of the place to have a registered company to fulfil certain requirement to get listed publicly. Certainly, Hong Kong does not have a restriction of the nationality to register a company there.

where else? Silicon Valley? Stockholm?
Lots to discover! These are real matters to discover. It will help make a solid decision!~

OR
do you even need to register a company to start working on your ideas?