With regard to the sort() function in the Search class, I would like to be able to specify multi-attribute sorting, like so:
$search->sort(['date' => 'DESC', 'attribute2' => 'ASC', 'attribute3' => 'DESC', 'attribute4' => 'ASC']);
It appears that the current code only allows for specifying sorting by one attribute, or by multiple attributes but all with the same sort direction.
It also appears that specifying the sort direction ('ASC' or 'DESC') as anything other than all-lowercase results in an error. It would be preferable to be able to specify these in uppercase, consistent with SQL conventions.