Just watched a Yale lecture answering the question about why there was no revolution in Britain in 1848. The basic answer is that Britain's identity played a part (we're not French and not Catholic and not Irish, we reform, we're not absolutists), and that was used to keep rebellion at bay (even if it was brewing). This was mixed in with a hatred for the Irish.
Is this the consensus among historians? What are other reasons for this?
Richard J. Evans covers this quite well in The Pursuit of Power. Essentially, there was a lot of rioting and tension throughout this period, but unlike the rest of Europe there was "gradual" release of tension as well as oppression. This came, for instance, in the 1832 reform act. While objectively it did not expand the franchise a great deal, it did cause a little of the tension to be released. This combined with not being as repressive as the rest of the monarchies of Europe.
There is something then, in what you say about a reforming character, but Evans points out that this is sometimes overplayed: there was just enough done to stop rioting and protesting spilling over into rebellion.