I'm noticing single line breaks appear to be double in post editor, but they preview/post as single, you have to hit two to double space paragraphs, but after first preview they become normal. Think this is the wysiwyg mod. WYSIWYG has been problematic, the core feature in 2.0 is buggy and not recommended. You're using the SMFPacks WYSIWYG Editor mod, first time I'm seeing it, but wouldn't be surprised if it also has problems. I'm seeing a lot of server errors in Subs-Posts.php, they seem to occur in clusters, but don't think they're related to this. I'll drop you back to php 5.6, see if it helps, some of the older mods aren't updated for php 7.
Re: backups, most hosts do server backups daily, but often only keep them for 2-3 days, then they're gone. Some will charge you to restore db from server backups. My host (Crocweb) runs R1Soft in cpanel, it backs up everything in the account daily and keeps it for 30 days on remote servers, so even if host server gets nuked, backups are elsewhere. I also have cronjobs running that backup all dbs daily and saves them 30 days on host server. This wouldn't work for you due to the size of your db and current disk space limits.
I'm going to block ip 36.57.*.*, keeps logging errors. You don't have any members in that range. It'll be in .htaccess if you need to remove it.