One wing tip is forward by 3/8 compared to the other? If that is so then you want to correct that before attempting to fly. I'd say that an 1/8 to 3/16 on a large model is sort of OK but 3/8 will definetly lead to some crabbing in flight issues and probably a slight difference in how it responds to turns to either side.

Oddly enough the stabilizer being skewed isn't as big a deal other than visually and the fact that you'll KNOW that it's that way..