or as we say in Iceland,
You may have underpitched which may result in some off-flavors and aromas that were not initially designed in this recipe, but you like the end result.
I do not recommend that you pitch more sugar/yeast, since the flavor is already in the beer.
Over-airating can result in off flavors aswell, so you may look into the aeration stone time aswell.
Underpitching results in some flavors that may or may not be desireable, it all depends on what you are trying to make.
Your final gravity will probably be higher than usual since this is such a high gravity beer, so don't let high FG fool you (I would expect somewhere around 1.020-1.023).