IgorG,
Учту Ваше замечание, спасибо.
Based on my recent experience:
the most correct way of your - the wrong way, in my opinion.
Let me explain my point of view:
1. I have 15 service plans. I know the key combination "copy - paste", but this is too much.
2. Changes in the config of service plans will not be affected on locked for editing subscriptions. For example, if I change the memory limit on the domain, his subscription will be impossible to change even if you change the service plan.
3. Because I'm changing sendmail_path in all domains, I, naturally, modified /etc/php.ini. Php.ini template for new domains is taken there, and the directives from (

) are added to it.
4. Most importantly, if I add here (

) directive, which is already in the default php.ini, then plesk core NOT overwrite it, and add it as a new row. This will cause a crash the web server, followed by a denial of service.