Considering the faster battles take around 30 seconds and the slower ones can cost you easily 3 minutes, you have to decide at the beginning if you even want to play that map.

It is pretty obvious, but when the game starts and pans over the map you have to create a road you want to take already, try walking on the outermost lines as they do not have the navigation at some point and jump over a level sometimes.

I would restart every map that has less than 4 treasures, especially considering that the world has 10 layers or 9 at the shortest. The second thing one has to consider is the ? fields. They should be in between the treasures to lower the chance for fights that can take longer. Avoid all boss fights. Only the minotaur can be finished pretty fast.