First of all we want to congratulate you on the great work you're doing.

That said, our devs have made us part of some recommendations for mdbootstrap:

• Ensure the use of !default in all mdbootstrap variables to allow easier customization (4.4.1 is a great improvement since the 4.4.0.beta but it was reported to me that a few are still running around).
• Ensure that the body fonts use the bootstrap variable $font-family-sans-serif or at least ensure that the typography of mdbootstrap is modifiable, like:

$mdb-body-font-family: $font-family-sans-serif !default;
body {
font-family: $mdb-body-font-family;
font-weight: 300;
}
// or
$mdb-body-font-family: 'Roboto', sans-serif !default;
body {
font-family: $mdb-body-font-family;
font-weight: 300;
}

• Ensure that bootstrap border radius declarations (for example .border-0) do apply for (.author-box, .badge, .jumbotron, .list-group .list-group-item, .navbar, .navbar-toggler). Currently they do not, since mdb.css is imported after bootstrap.css, hence overriding the declarations.
• Ensure MDB-Pro downloads in the user profile have the correct semver (we downloaded at some point MDB_Pro_4.4.0.zip but the version in the README.txt said 4.4.1). ¿Is there a delay on publication?
• mdb-select of MDB-Pro is very hard to use for accessibility (screen-readers, keyboard only users). Visually you cannot use the keyboard to select options (well, you can but there's no visual indication of it).

Once again, we wish to thank you for your work, and are waiting anxiously for mdbootstrap react ;-).