How to make laravel app more SEO friendly

I want to make my laravel 5.8 / blade/ Bootstrap v4.1 my voting app more SEO friendly and for this I make 1) url of my site like:

http://site/vote/in-greek-mythology-who-turned-all-that-he-touched-into-gold

2) I add meta description and keywords into my pages:

@extends($frontend_template_name.'.layouts.frontend')

@section('meta_content')
    <h1 class="text-center">
        @if(isset($site_heading))<span> @endif</span>
    </h1>
    <meta name="description" content="" />
    <meta name="keywords" content="" />
@endsection
@section('content')
...

3) What else can I do?

4) Are there some sites like https://validator.w3.org/, but SEO friendly checking ?

Thanks!

via Chebli Mohamed