I've sat under his ministry for almost 9 years, heard almost every sermon, read all his books and seen the fruit of his ministry (tons of testimonies coming in), so I think I'm qualified to say something:
He does have WOF influences but he does not believe or preach everything WOF teaches. Also, I think any preacher growing up who wants a successful ministry with Holy Ghost power would inevitably read 'WOF' type books, simply becos the other types of traditional books just lack the 'power'.
That aside I can tell you that his real calling is to preach the gospel of grace the way it was originally preached by Paul -- pure and unadulterated to the point that some people misunderstand you ("What!? Shall we sin more that grace may abound?!")
So his main topics are grace vs law, righteousness, forgiveness and most of all, the finished work of Jesus at the cross. If he teaches other topics, such as healing or tithing, then it would be from the perspective of grace.
A reason he is so successful with thousands queing up for hours to hear him every Sun is that he has a strong teaching gift. He is able to draw Christ out of both the new and esp the old testaments. IOW, he is able to give his listeners the Emmaus Road experience -- making them see Christ in the Word.
If anything, he points people to Jesus and His finished work. His heart is to exalt Christ in the church, or as he would say, bring the Ark back to the church.
Anyone who has listened to him with an open mind and heart for some time will find all that I've said very true.
I'm not here to exalt the man, but if you want more of Jesus in your life, he is the man to point you to Him and to reveal Him to you.