It is tempting to do some substantial rewrites during migration to a new platform. Experience has shown that it is rarely a good idea. Just the migration itself is enough disruption – ActiveRecord (AR) and ActiveSupport 2.3 to 3.1, Rails controller syntax to Padrino/Sinatra, Ruby 1.8.7 to 1.9.2 and the string encoding issues.
As mentioned in a previous post, I did benchmark some of the alternatives. ERB to Erubis is a minor change. I have already migrated from the Prototype Javascript library to jQuery’s compatibility mode. As templates are edited, I’ll move to jQuery native mode and make use of jQuery Unobtrusive JavaScript (UJS).
I’m tempted to move to more or all rendering and some data caching on the browser with the server just rendering JSON. That will wait until after the migration to Padrino.