His English Strong Ale took Best of Show honors at our festival last year and was awarded a gold medal at AHA Nationals. It has been my recent experience that when brewing high gravity beers, alcohol is a greater constituent in the flavor profile. This should always be considered during recipe formulation. Furthermore, the residual sweetness of these beers is also an aspect of their character that should not be overlooked. There are nuances to manipulating the array of alcohols and sugars which in the end will define all high gravity beers.
Adjuncts create diversity.
We've all tasted mead honey can add both alcohol complexity and a unique residual sweeness. Both of these items are ideally suited to the home brewer. They'll help you to achieve higher gravities while at the same time diversifying alcohol complexity and influencing residual sweetness in the flavor profile. Don't overlook the brown sugars, molasses, corn sugar, etc. I hope these simple ideas will help you to produce more complex and diverse high gravity beers.