How to optimize laravel query?

Question

Laravel

Hello, please help me transfer my request to Eloquent to the maximum.
At first the request was completely "raw", now it has been transformed a little, but it turned out not very beautiful.

#
        $subscriptions = Subscription::where('user_id', \Auth::user()->id)->lists('entity_id')->toArray();
        $views             = View::where('user_id', \Auth::user()->id)->lists('post_id')->toArray();

        if ($subscriptions) {
            $entityIds = '(' . implode(', ', $subscriptions) . ')';
        }

        if ($views) {
            $ids = '(' . implode(', ', $views) . ')';
        }

        $result = Entity::leftJoin('countries', 'countries.id', '=', 'entities.country_id')
            ->leftJoin('posts', function($join) use ($entityIds, $ids) {
                if ($entityIds) {
                    $join->on('posts.entity_id', 'IN', \DB::raw($entityIds));
                }

                if ($ids) {
                    $join->on('posts.id', 'NOT IN', \DB::raw($ids));
                }
            })
            ->selectRaw('
                entities.id,
                entities.alias,
                entities.type,
                entities.name,
                countries.iso_code_3 AS country,
                count(posts.id) AS unwatched
            ')
            ->get()
            ->toArray();

The whole problem is that initially I had a select in the join:

LEFT JOIN (
    SELECT ....
) as Q2

In general, I need to count the number of records from a related table.
How can I simplify what I got?