Welcome to the JavaRanch, Kesava!
It can be a lot harder to migrate from WAS to Tomcat than to go in the opposite direction. For example, you mentioned "deploying all your ears". That won't work, because Tomcat does not implement the entire
J2EE stack, and one of the unsupported features is the EAR format. Tomcat can only handle WARs. Likewise, Tomcat does not contain its own EJB, JMS or mail facilities.
On the plus side, Tomcat is generally faster to start up and can be expected to use less resources, since it doesn't have to load and initialize all the features of the full stack.
The secret of how to be miserable is to constantly expect things are going to happen the way that they are "supposed" to happen.
You can have faith, which carries the understanding that you may be disappointed. Then there's being a willfully-blind idiot, which virtually guarantees it.