I don't think we should bother with any utilities but education. We should expand the southern area and add an elementary school there (be sure to adjust it's funding though). Also in the southern area we should keep a large block empty and put the casino there; the rest of the block should be for commercial when we need more of it.
We shouldn't add anymore housing to the northern area because it will all be polluted eventually; just add industry's up there.
Tip: Look at the RCI under graphs, it's very helpful.