I've got the following recipe for a honey whole wheat bread-machine bread:  1-1/3 cups warm water 1/2 cup honey 3 tablespoons butter 2-2/3 cups whole wheat flour 1-1/3 cups bread flour 1-1/4 tsp salt 2 tsp yeast   I'd like to substitute maple syrup for the honey to produce a maple wheat bread.  Can I substitute one for one, or do I need to make adjustments?  In particular, will I need to increase or decrease the amount of water used? 
Water solubility isn't enough - that gets the flavour into the water but says nothing about whether the flavour gets to the food. Consider salt as an extreme example.   You may get somewhere by putting the source of flavour on top of the food being cooked. There are recipes that do this with mint for example, though they normally add more mint at the end.  The ginger you mentioned may work in a similar way, but testing is difficult as this approach tends to scent the kitchen or even the whole house, so you perceive the flavour even before the food is served.  