Bit of an old post and I see it got no response, but I was just about to post the same thing.  I started two different games, explored a decent chunk of land around my starting area, and didn't find a single quest.  I've played maybe a dozen or more games prior to this and even with the default quest setting by this time I've usually seen at least 3 or so.

I have Quest Frequency set here to "Plenty."

Working as intended?

I think certain categories of options don't work for pre-made maps - most probably only for random maps.  But still, you'd expect such a big map to have more placed quests.