Now that's a good argument. But even taking that into consideration, Great Britain was directly responsible for the lack of democracy in places such as India, and joining that to the fact that even within Great Britain itself only around 35% of the adult population could vote, it is still rather hard to consider early 20th century Britain as a "democratic power".
Now, it seems to me that we have two slightly different views on what constitutes democracy in early 20th Century Europe. Now, while I agree that the size of the electorate is important, In my opinion, the powers held by the elected representatives is more important. Now, as an example, the UK was the only great power (according to Hastings's Catastrophe) to debate the decision of whether to go to war in Parliament (or the national equivalent) and it certainly was not a clear cut case.
I doubt that either of us will reach a consensus on democratisation, but in my opinion the key indicator for democracy prior to acceptance of universal suffrage was the codification of rights and liberties of the people, codification of the rights (including freedom of speech) of an elected Parliament and the limitations to the absolute power of a non-elected head of state. These things were developed and integrated in British Society from the 13the century onwards; many of the rights established in the late 17th century (such as the bill of rights) are still regarded as the cornerstones to (British) democracy.
Judging British democracy by its lack of Universal Suffrage in a time, when in other nations, executive power was held by a few non-elected individuals is a little disingenuous from my perspective. Though, I am enjoying your views on this matter