In an ideal situation, you would test your installation of Zikula in a local (development) environment before moving the entire site into "production". This process is called deployment.
Symfony provides documentation for this process here.
Before deploying your site, you should remove all unused Zikula extensions.
Another recommended step is to run
composer dump-autoload -a (authoritative mode). This will allow all supported
Zikula core classes to load faster. (see composer's autoloader optimization).
It will also pre-cache all annotation classes in supported classes which will also speed up loading.
Beware however, as classes that are generated at runtime will not autoload and this could cause issues.