I have a web application already built which needs a better design. It is built using Ruby on Rails and some of the functionality is done using jQuery/AJAX. I am looking to eventually convert most of the site to use AJAX so this should be also taken into consideration in the redesign. There are a couple of different pages the application presents to the user, I'm looking for suggestions about design, how the information can be better organized/presented, etc.
The HTML is spread throughout hundreds of Ruby on Rails files, but there are only a few different views that are presented to the end user. I would estimate that this would only take a day or so of design.