The Long 19th Century (1789-1914) has always been my favorite.
That would be #1 on my list of most overrated centuries. It's frustrating how much attention the 1800s gets, while the more than 100 years between the end of the 30 Years' War and the start of the 7 Years' War is largely neglected. I've just always found struggles of ideology and nationalism to be far less intriguing than dynastic power politics. The period encompassing the late 17th and early 18th centuries - with its constantly shifting alliances, wars of succession, and conflicting political and religious interests of the various states - was truly the peak of European diplomacy and grand strategy. Not to mention the peak of art, music, and culture on the continent.
Personally, I could never much bring myself to care which wealthy Italian family was currently king of the hill or which royal cousin has the more "legitimate" claim —none of those people would have been interested in
me. I do agree that the late seventeenth/early eighteenth century has a lot to offer, though.