What did Ilduce say?
I claimed half the world? Really? Actually, as i remember, I claimed barely a fraction of what the British Empire of old once possessed, and they had something like 1/4th of the world at their height. My claims were Canada, new England, Iceland, Portugal, North Africa (not sure how much I calimed here, and im too lazy to check), and India. When I reduced my claims, I was down to Mahgreb, Portugal, Sahel, Isles, Ceylon, and possibly some other territory.
So you see, even when I reduced my claims, I still claimed Portugal and those two north african territories. Portugal has been a long time ally of Britain, especially in the napoleonic wars, and rather than see them fall to a less friendly country, I had decided to bring them into my country as an equal state, just as Mahgreb was (well that defeats your Imperialism claim. Its definition involves certain parts of the empire being treated unequally which was not the case here).
So basicly if the tide turns and the AGGRESSOR of this conflict is about to be totally and utterly defeated with no territory remaining, you will step in to save the nation that started this conflict...I fail to see how this is 'keeping the peace' in Europe as you put it, by prolonging a conflict rather than let it take its course and end with the total defeat of one of the states.
It seems you are using this conflict as an excuse to make threats and exercise the power and influence of the BA. I ask again: Stay out of western European Affairs, especially when you are threatening a country to not defend itself.
On the event: Well on one hand you have +10% ultra influence increase, 2 armies, core on a north african territory, and war with britain (and NATO). In the short term, this seems best doesnt it? Easy armies, easy territory, but a long, painful war...and on to the second option. well you get 2 factories, and you lose one stability. So what? use a turn of your new factories to replace it. You avoid war (arent you the one that advocates European Peace? YES.), and gain some extra industrial strength. You still have your claim on Sahel and Portugal, and your set up to become a darn good sized power to Rival Britain and the others.