Hi @cole
Thanks for adding this as a feature request. It seems minor but the splash page is the user's first impression of the service and having some simple customization lets them know they are in the right place before they enter credentials.
In general, I'd just like something that is fairly basic, easy to maintain, looks nice on any browser or device, advertises the service features (because as a sysadmin, I have to sell it too!), and an easy place (like a site footer) to swap in simple things like organization/unit/project name, logo, legal statements, and a link for more information or support.
JupyterHub does this by overriding Jinja templates and RStudio Server has the login.html file. Neither are perfect but they do make my life a little easier without having to search for web developers.