This pretty much covers it... however, there are things to consider.
If your website accidentally adds rel="noopener noreferrer" directives (on internal links), this would be treated as Direct Traffic, rather than as Internal. This can cause some havoc with your stats.
Also, if you have things like Marketing Emails or Newsletters, links in these can be split between Direct Traffic (coming from program based mail readers that are installed on computer) or as Other Traffic (coming from web based mail readers like gmail). In these cases, you want to make sure that you are passing campaign data on all links to ensure that the proper channel attribution is applied. (So this is less a use case for, but rather a potential pitfall to try and avoid)
As for Internal Traffic, depending on your setup, there may be "external domains" that you want to be treated as internal (maybe you are using an external payment flow provider, and it's not set up on your specific domain)... you may want to add these specific domains to your internal URL filters so that you don't have an exit and re-entry within your purchase flow....
Or maybe you have a network of sites that are being tracked in a global tracking suite, you would want to treat the network as internal (but you can also do some pathing tricks using server or a prop/evar tracking which site you are on to see how users are moving back and forth across your domains)
There may be some other specific considerations that others are using... first and foremost, you need to be aware of your site flows and what makes sense to you and your users.