Were there former colonies that might instead have become integrated parts of the United Kingdom?
Short answerMalta is the clearest example in the discussion: where a territory itself sought integration, Britain could have considered a French-style constitutional path, but otherwise self-determination should govern.
NotesFormer colonies should determine their own status, and Britain should not reverse self-government for convenience. The answer then considers a different path in which territories seeking integration might have become parts of the United Kingdom rather than separate states. Malta is the main example because a referendum had raised the prospect of joining the UK. Maltese representation could have changed debate in the House of Commons and made British politics more varied. The answer is explicitly counterfactual and personal, not an argument that decolonisation generally should have been prevented.