Hmm.. Do you get BB for burning colonies?
Otherwise I would burn everyone you can't get a land bridge to pretty soon and then take the 5 portugueese outer provinces so you lock them in. Ireland is not what you should worry about. Cripple the biggest threat first. Unlike in a war where you should go for the weakest first.
And you could have gotten Portugals WE up high if you have let them siege for a while more, attrition is the biggest thing for WE. And Portugal often have problem with manpower, you could perhaps have bled them dry without even fighting a battle.
And sure that Ireland didn't guaranteed Portugal? It just doesn't feel right.