So why not consider outside London if you’ve heard that London is a mini Asia (for the record, London is very diverse). It may come as a shock to many (I doubt it will to you Mirage) but there are many more cities in England apart from London-Leeds, Birmingham, Bristol…and so on.
Each country, each region has it’s own plus and negatives that’s simply the way it works.
As others have said, The UK will have a shake up of visas/immigration that is set to hit in April 2011, I’m not 100% sure if this will effect your circumstances but it’s worth looking into.