I tended to cheat and do it both ways...
I would send a serious query that would impress a business-type and then, if I didn't hear back in three months (which happened often) I would follow it up with a quirky, humorous one that almost always got a hand-written answer (even if it was a no, I usually got a request for my next one.) Because the humor was about the
business rather than about my book, and was sympathetic toward their being overworked, it really made points.
But then we got an agent, and I had to stop writing queries
Pity. I really do enjoy writing a good query.