So far there is no reward for finishing part 1 quickly.
Goal 1: just a button
Goal 2: expand plot to the left of the "geode" mine.
50 wisp lanterns, 3000 royal points, 500k coins
Goal 3: gather glitter mushroom (prize from previous goal), make a gnomish omelette (glitter mushroom 5 tomatoes, 5 eggs, 15 minutes, kitchen), give omelette.
Goal 4: clear geode rock (2, 20 hits), gather garnet, gather deep mine stone (both from geode rock)
Goal 5: clear geode ore (1), gather gnomish silver, gather deep mine mud (from ore)
Goal 6: expand to geode mine, 3400 royal points, 700k coin, 54 wisp lanterns
Goal 7: posted once I find/make 5 more wisp lanterns.
End of Part 1.
Note: step 2 and 6 will require you to close the game and reopen for the expansions to be available.
Multiple drops of mine stone and mud from rock and ore. Sometimes get 1, sometimes get 2. I either got the rock/ore or garnet/silver. They never dropped both from 1 chop.