Thanks for the info, I wish I'd had it before I started my current campaign.
Playing as English, I immediately attempted to consolodate my control of the British Isles by capturing Wales, then Scotland then Ireland.
I made a treaty with the French (sorry to all English readers out there) and Spanish in order to secure my continental borders, and remained neutral with the HRE.
It took me ages to get to a position where I had enough income to no longer worry about the French and HRE, and to be able to expand.
Your info will certainly help in my next campaign, so I should be able to move faster.