That looks okay other then you should uncheck "Fetch on Auto-cron" since you are running a cron/task scheduler.
As a side note I went to your web site on two different computers and the load time on your site was over 15s (not your support site, your domain). I'm wondering if you need a heftier webserver than you are currently running if both are hosted on the same web server. I'm also wondering what the ping times between the webserver and the mailserver look like, and how many hops it is via traceroute. I do not see anything that would cause such a delay in the settings.
Side note it takes us about 5-10 seconds to open a ticket on our system which is an internally hosted webserver and using o365 to send email. We noticed a big jump when we migrated from internally hosted Exchange to O365 Exchange as it was around 1-2 seconds before we migrated.
