I recently had the problem that my SOLR Service was not starting all of a sudden. So I searched the internet and asked colleages but I had quite a hard time figuring out what the issue was. So here is a summary of possible reasons that you can check.
When you have created Components and you figure out later that they are used always in a bunch of e.g. 3, or you want to prepare a one-time-drag-and-drop experience for the editor even though several components are involved (like in a header or a footer) then the component renderer (introduced with SXA 1.8) is a good solution for you.
Do you have agreed on SLAs towards your website and authoring environments? When thinking about your Sitecore Infrastructure you have many opportunities to scale out. Let's take a look what we considered in our project.
Here you can find my presentation about 100% availability with a video taken from SUGPL in December 2017 and links to the single Blogposts that deal with that topic.
In case you run several websites in one Sitecore instance and need to distinguish users between those different sites here’s what we did.
When starting a project usually there are so many requests and ideas that you create ambitious Role concepts and rolling these out to all of your sites. After a while you see that not all features are really used. This was the point in time for me to get back to a more lean approach.
As any system, also your Sitecore installation will historically grow. And for sure, none of the users will tell you when he or she stops working on Sitecore or leaves the company. Also noone of the local administrators (in case you have some) will tell. So, to keep Sitecore a bit clean you can check for users that are not active in the system.