How to customize default wordpress editor?

I was looking for a solution to place custom metabox above the default editor and i’ve found the solution to my old question (how to customize the default editor with the wp_editor)!

The solution was to unset the default editor first. Then create another metabox to to place the content then use wp_editor to create new its new instance, simple isn’t it?

add_action( 'add_meta_boxes', 'page_meta_boxes' );
public function page_meta_boxes()
{

    global $_wp_post_type_features;
            //ive defined my other metaboxes first with higher priority
    add_meta_box(
        $id     =   'page_heading_meta_box',
        $title  =   __('Heading'),
        $callback   = array(&$this,'render_page_heading_metabox'),
        $post_type="page",
        $context="normal",
        $priority   =   'core'
        );
    add_meta_box(
        $id     =   'page_description_meta_box',
        $title  =   __('Description'),
        $callback   = array(&$this,'render_page_description_metabox'),
        $post_type="page",
        $context="normal",
        $priority   =   'core'
        );
    //check for the required post type page or post or <custom post type(here article)  
    if (isset($_wp_post_type_features['article']['editor']) && $_wp_post_type_features['post']['editor']) {
        unset($_wp_post_type_features['article']['editor']);
        add_meta_box(
            'wsp_content',
            __('Content'),
            array(&$this,'content_editor_meta_box'),
            'article', 'normal', 'core'
        );
    }
    if (isset($_wp_post_type_features['page']['editor']) && $_wp_post_type_features['page']['editor']) {
        unset($_wp_post_type_features['page']['editor']);
        add_meta_box(
            'wsp_content',
            __('Content'),
            array(&$this,'content_editor_meta_box'),
            'page', 'normal', 'low'
        );
    }
    }

In this way we have registered a new metabox called content . Now time to place the editor

        function content_editor_meta_box($post)
    {
        $settings = array(
            #media_buttons
            #(boolean) (optional) Whether to display media insert/upload buttons
            #Default: true
            'media_buttons' => true,

            #textarea_name
            #(string) (optional) The name assigned to the generated textarea and passed parameter when the form is submitted. (may include [] to pass data as array)
            #Default: $editor_id
            'textarea_name'=>'content',

            #textarea_rows
            #(integer) (optional) The number of rows to display for the textarea
            #Default: get_option('default_post_edit_rows', 10)

            #tabindex
            #(integer) (optional) The tabindex value used for the form field
            #Default: None
            'tabindex' => '4'

            #editor_css
            #(string) (optional) Additional CSS styling applied for both visual and HTML editors buttons, needs to #include <style> tags, can use "scoped"
            #Default: None

            #editor_class
            #(string) (optional) Any extra CSS Classes to append to the Editor textarea
            #Default:

            #teeny
            #(boolean) (optional) Whether to output the minimal editor configuration used in PressThis
            #Default: false

            #dfw
            #(boolean) (optional) Whether to replace the default fullscreen editor with DFW (needs specific DOM elements #and css)
            #Default: false

            #tinymce
            #(array) (optional) Load TinyMCE, can be used to pass settings directly to TinyMCE using an array()
            #Default: true

            #quicktags
            #(array) (optional) Load Quicktags, can be used to pass settings directly to Quicktags using an array()
            #Default: true
        );
        wp_editor($post->post_content,'content');

    }

Now you can fully customize your editor! This is how it looks now. Hope it is useful for you too!