Possibly. Also there is issue with PHP settings with LSPHP handler. I managed to get it working. I disabled all PHP handlers except LSPHP by OS vendor and enabled LVM selector (then users are able to choose PHP version and extensions using LVM selector and they don't see Plesk PHP settings). Actually I'd prefer to use (or provide users possibility to use) native Plesk PHP selector with LSPHP. Problem is Plesk PHP selector isn't designed to handle cloudlinux altphp/LSPHP extensions like pdo, opcache and so on.
No, it's installed and even working properly (on service nodes extensions still can be accessed directly using search bar), however shows bad refferer if I'm trying to access it standard way.
So, I'm able to make provision via WHMCS using Plesk Multi Server with Cloudlinux and it's working, but multi server is still too fresh as I see. Hope for soon bugfixes.
I will try also MySQL Governor today.