[DOC] readme: add a tag line, improve readme

README.md

@@ -1,15 +1,19 @@
 <h1 align="center">🦉 <a href="https://odoo.github.io/owl/">Odoo Web Library</a> 🦉</h1>
 
+_A web framework for structured, dynamic and maintainable applications_
+
 ## Project Overview
 
 The Odoo Web Library (OWL) is a small
 UI framework intended to be the basis for the [Odoo](https://www.odoo.com/) Web Client, and hopefully many
 other Odoo related projects. OWL's main feature is a _declarative component system_, with QWeb as a template engine, asynchronous rendering, and an underlying virtual dom.
 
-If you are interested, you can find a discussion on what makes OWL different
-from React and Vue [here](doc/comparison.md)
+**Try it online!** An online playground is available at [https://odoo.github.io/owl/playground](https://odoo.github.io/owl/playground) to let you experiment with the OWL framework.
 
-## What makes OWL different
+## OWL's design principles
+
+OWL is designed to be used in highly dynamic applications where changing
+requirements are common, code needs to be maintained by large teams.
 
 - **XML based**: templates are based on the XML format, which allows interesting
   applications. For example, they could be stored in a database and modified
@@ -22,10 +26,9 @@ from React and Vue [here](doc/comparison.md)
   for various reasons (security/deployment/dynamic modules/specific assets tools),
   it is not ok to use standard web tools based on `npm`.
 
-
-## Try it online!
-
-An online playground is available at [https://odoo.github.io/owl/playground](https://odoo.github.io/owl/playground) to let you experiment with the OWL framework.
+Owl is not designed to be fast or small (even though it is quite good on those
+two topics). If you are interested in a comparison with React or Vue, you will
+find some more information [here](doc/comparison.md).
 
 # Example