If you plan to sweeten, you can add more blueberry flavor back with a blueberry f-pac (flavor pac?). Anyways, here is a good post on f-pacs:
Basically an f-pac is using some fruit (in your case blueberries) to make a sweetening "package" that includes this fruit to add back the original flavor to the wine. You add it after you have stabilized the wine (ensuring the sweetening does not start the fermentation back up). Use potassium sorbate to stabilize. An f-pac generally means that you'll need to let it clear again, although it may not take as long as the original wine.
Wade had a good post on how to make an f-pac, but I can't seem to find it. Anyone?
If you don't plan on sweetening, then I don't know of any other way to add back flavor barring extracts. Aging can often bring back flavors that have gone missing though. Sometimes at early rackings the wines are pretty harsh and the flavors don't really present themselves.