Hi Ryan,
We're working hard to bring military symbology to web applications without the need to publish a map service using the dictionary renderer in ArcGIS Pro. We are releasing this capability in multiple stages. The ArcGIS API for JavaScript version 4.13 (due to be released next month) will include a new Dictionary Renderer API, allowing you to use a web military dictionary style to symbolize point features or graphics. More information on this will be published closer to the release date. In the future we will be adding support for lines and areas, and direct support in ArcGIS Online and Portal for ArcGIS.
Meanwhile we have made several improvements to dictionary styles over the last year, and these improvements are also available when the style is used throughout the platform, whether it's ArcGIS Pro, the Runtime SDKs or JavaScript API. These styles are now configurable and customizable. Read more about it here: https://pro.arcgis.com/en/pro-app/help/mapping/layer-properties/dictionary-renderer.htm, and if you're interested in customizing styles, or even taking a deeper dive into a dictionary style, I recommend checking out the Dictionary Renderer Toolkit for ARcGIS Pro on GitHub: https://github.com/Esri/dictionary-renderer-toolkit.
Stay tuned...
Kerry