I have installed postfix on my debian box, and works ok. I can send mail via my windows box to external email address using the MTA. This is a copy of main.cf

# Do not change these directory settings - they are critical to Postfix
# operation.
command_directory = /usr/sbin
daemon_directory = /usr/lib/postfix
program_directory = /usr/lib/postfix

smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
setgid_group = postdrop
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no
myhostname = pulse.nuphrax.net
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = $mydomain
mydestination = $myhostname localhost.$mydomain localhost $mydomain
mynetworks =
inet_interfaces = all
relay_domains = $mydomain
home_mailbox = Maildir/
mailbox_size_limit = 0
recipient_delimiter = +

I was just wondering if there is anything that I need to add or remove or alter to make it more secure, work smoother etc?