I visited the UK a few months ago after a hiatus of about 4 years and, on balance, I simply hate the place.
There are great things about the UK - sport, countryside, mountains, rivers, parks, animals, gutsy people, education, healthcare, history and all that. But for me, everything is ruined simply because of crime and lack of respect for law and order.
Like me, you will have gotten used to, and taken for granted, the peace, safety and security of Singapore. I dread having to go back to the UK, where wandering into "no go" areas in the dark could get you mugged or worse. Kids hanging out by shops causing trouble. Vandalism. Drugs. Drunken fights. Getting beaten up just because you looked at someone the wrong way. To me this means you simply cannot enjoy your life no matter how much you try. In the UK, you will come across thuggish behaviour and just one experience is enough to make you worry about your kids.
Let's not even mention the high taxes we would have to pay for the "privilege" of living there.