[doc] slightly reorder the chapters & improve TOCs for better navigation

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

docs/index.rst

@@ -11,21 +11,37 @@ SearXNG can be used over Tor for online anonymity.
 Get started with SearXNG by using one of the instances listed at searx.space_.
 If you don't trust anyone, you can set up your own, see :ref:`installation`.
 
-.. sidebar::  Features
+.. sidebar::  features
 
-   - Self hosted
-   - No user tracking
-   - No user profiling
-   - About 70 supported search engines
-   - Easy integration with any search engine
-   - Cookies are not used by default
-   - Secure, encrypted connections (HTTPS/SSL)
+   - :ref:`self hosted <installation>`
+   - :ref:`no user tracking / no profiling <SearXNG protect privacy>`
+   - script & cookies are optional
+   - secure, encrypted connections
+   - :ref:`about 130 search engines <configured engines>`
+   - `about 60 translations <https://translate.codeberg.org/projects/searxng/searxng/>`_
+   - about 100 `well maintained <https://uptime.searxng.org/>`__ instances on searx.space_
+   - :ref:`easy integration of search engines <demo online engine>`
+   - professional development: `CI <https://github.com/searxng/searxng/actions>`_,
+     `quality assurance <https://dev.searxng.org/>`_ &
+     `automated tested UI <https://dev.searxng.org/screenshots.html>`_
 
-.. sidebar:: info
+.. sidebar:: be a part
+
+   SearXNG is driven by an open community, come join us!  You can :ref:`donate
+   <donate>`, but much more we appreciate contributions.  Don't hesitate, no
+   need to be an *expert*, everyone can contribute:
+
+   - `help to improve translations <https://translate.codeberg.org/projects/searxng/searxng/>`_
+   - `discuss with the community <https://matrix.to/#/#searxng:matrix.org>`_
+   - report bugs & suggestions
+   - ...
+
+.. sidebar:: the origin
 
    SearXNG development has been started in the middle of 2021 as a fork of the
    searx project.
 
+
 .. toctree::
    :maxdepth: 2
    :caption: Contents