Try a harley rake or a tiller and loosen up the top layer of dirt. Then go over with a heavy drag and then a regular drag. The problem of uneveness seems to come from busy spots(positions, sliding paths, etc..) if you can loosen the high spots and move the dirt into the low spots, you porblem should go away. After you use the field, it's a good idea to take a rake and push the dirt back into the low areas or even drag the entire field. Once you do that, wet those areas down real good and they should harden up like the rest of the field.
This may sound daunting but there is really no easy way to do it. Once you fix the problems, keep up your daily maitenance and it will be much easier in the future.
Hope this helps,
Jon
www.hardballcoach.com