SNI support for mail server

asking for some opinion regarding domain SNI support in postfix & dovecot.
apparently i am using a manual way to do it,
Create a site call mail.example.com and enable Letsencrypt SSL, & add

DocumentRoot "/var/lib/roundcube/public_html"
Alias "/stats" "{DOCROOT}/stats"​

to Apache Directives for Roundcube webmail.
Added in /etc/postfix/main.cf

tls_server_sni_maps = hash:/etc/postfix/domain_ssl.map​

/etc/postfix/domain_ssl.map

mail.example.com /var/www/mail.example.com/ssl/mail.example.com-le.key /var/www/mail.example.com/ssl/mail.example.com-le.crt​

run "postmap -F hash:/etc/postfix/domain_ssl.map && systemctl restart postfix"
create /etc/dovecot/conf.d/99-ispconfig-custom-config.conf

local_name mail.example.com {
ssl_cert = </var/www/mail.example.com/ssl/mail.example.com-le.crt
ssl_key = </var/www/mail.example.com/ssl/mail.example.com-le.key
}​

restart dovecot
and create a bash script to run "postmap -F hash:/etc/postfix/domain_ssl.map && systemctl restart postfix" and add the script to post-hook for acme.sh cron job.
need clarification if i am doing it a correct way for ISPConfig or there is a better way to do it coz i don't find anything in the web gui. it's pretty troublesome to do it every time when create a new mail domain.