Our server is HTTP now and we are getting some issues that the map services could not loaded in web apps or when embedded in WordPress, because story map templates and WordPress are using HTTPS. It's anoying that we have to tell the users to remove the "s" in the URL. So I am wondering if we should change it to HTTPS? I am not expierenced and I would like to hear from you. Any pros and cons?
Yes, we strongly recommend that you enable your ArcGIS Server site to be HTTPS. It is a best practice to try and make your Server site as secure as possible. In fact, starting at the 10.4 release, the default setting for ArcGIS Server's security protocol is HTTP and HTTPS.
Hope this helps,