Good morning Rai
To do the former option would be easier, in part.
S&F Pro already has the option to sort results by Post Type, so all you need to do is to format the results differently.
The standard results.php is structured like this:
<?php
while ($query->have_posts()) {
$query->the_post();
?>
OUTPUT THE POST HERE
<?php
}
?>
Instead you would do:
<?php
while ($query->have_posts()) {
$query->the_post();
switch (get_post_type( get_the_ID() )) {
case 'Post Type A':
?>
OUTPUT THE POST HERE if it is Post Type A
<?php
break;
case 'Post Type B':
?>
OUTPUT THE POST HERE if it is Post Type B
<?php
break;
case 'Post Type C':
?>
OUTPUT THE POST HERE if it is Post Type C
<?php
break;
}
}
?>
You would have a little bit more code if you needed to detect the start and end of the output of each post type (for example to start a background box or add a sub-title.
As to sort options, I do not know.
.
