The economic value of having colonies in the first place was for 3 main reasons
1) attain cheap labour from the native peoples
2) acquire cheap raw materials to bring to the homeland (Europe)
3) open up new markets to trade with
the first two were vital in Britains industrial revolution. Without cheap raw materials, and cheap labourers, the factories and refineries in Britain would have costed far more to maintain and keep supplied. This, in turn, would have slowed down production considerably. There is no doubt in my mind that the industrial revolution would still have taken place in Britain with or without the colonies, but WITH the colonies the process was sped up considerably.
Overall, cheap labour and raw materials attained through Britains colonial interests sped up the industrialisation of the UK.
A major problem for the United States after the Revolutionary War (1775-1783) was that tens of thousands of Loyalists, due to the climate of violence and fear that still existed after the conflict (particularly in the South), fled the country, retreating with the British army to Britain and other parts of the British Empire (Jamaica, Bahamas, India) and also to Canada, settling primarily in the regions of Nova Scotia and New Brunswick. Since those Loyalists were often wealthy and educated, and they had been part of the thriving and cohesive upper class that controlled much of the industry and the commerce in areas such as New York or Boston, the social structure of the colonies changed significantly after their departure.
