Step by Step Guide to Quests

Ironically, after about 8 weeks of doing both types of quests, my capital has Inquisitive Populace but not Block and Tackle. My second city, after about 4 weeks, got both on the same day...same level tavern as my capital. My newer cities have only been doing quests for a couple weeks (same tavern level), and no discoveries. So, in my experience, Inquisitive Populace was the easier of the two to get.

I finally got Block and Tackle in my capital today after, yes, a trade quest. Only took 9 weeks. 

Rymal,

Yes, currently there are only the 2 Discoveries that you can get from Tavern quests. As Rill said, the only reason to do quests after that is if the quest offers something you want in return for something you have extra of. For example, exchanging basic resources you have plenty of or sending out scouts in return for advanced goods that you could use.

The 2 discoveries 'Inquisitive populace' and 'Blok and Tackle' are really only worth getting when the city is small.

For a city with level 20 resource fields the extra you can gain collecting is less than 1%, and likewise a city that have the consulate up to 20 (15 squares distance) do not get much advantage by adding 2 squares more.

So pray you get them early, when they are valuable enough to help you grow.

Also remember that collecting make you vulnerable, if you rely on collecting to feed your city then an attacking army can pretty much vipe you out just by blocading your caravans.

best regards
~ Angua Whisper