When in Model Builder, it would be really useful if Sub Models were highlighted as being submodels and not just another step/tool in the chain. When my colleagues are editing/troubleshooting models that I have created, it's not always inherently obvious to them that there are submodels present unless I do something like the below. A simple highlighted border around the yellow tool symbol, or asterix against the name with a label. Some idea examples below.
Current default display:
![LindsayRaabe_FPCWA_1-1678842530610.png LindsayRaabe_FPCWA_1-1678842530610.png](https://community.esri.com/t5/image/serverpage/image-id/65280iEF17BE0AA5F6DBD7/image-size/medium?v=v2&px=400)
Submodel with border:
![LindsayRaabe_FPCWA_2-1678842545556.png LindsayRaabe_FPCWA_2-1678842545556.png](https://community.esri.com/t5/image/serverpage/image-id/65281i92365244486EB5D6/image-size/medium?v=v2&px=400)
Submodel with Asterix and associated label:
![LindsayRaabe_FPCWA_3-1678842566463.png LindsayRaabe_FPCWA_3-1678842566463.png](https://community.esri.com/t5/image/serverpage/image-id/65282i294F2FE21E3212E4/image-size/medium?v=v2&px=400)