I'd use the Type tool, instead of hand drawing the lettering. It's too hard to read.
There are some more "organic" typefaces that would fit this piece.
Set type isn't going to integrate any better than what's there, unless you know enough about Photoshop to play around with distortion and textures (which I'm betting you don't).
What you have to do is draw the words, not write them. This is an incredibly common problem among beginners; as soon as there are words in a picture, your brain switches from visual to text mode, and you end up using your regular handwriting. I'd take madster's suggestion about playing around with fonts, but once you have something you like, print it out and then hand draw it on you picture. Try to forget you're drawing letterforms and treat it like any other arrangement of shapes.