We are rolling out a new beta which includes a beta-only experimental setting to demonstrate initial support for building entities from filled forms. If you build a form according to the entities specification (you can use this pyxform branch), you will be able to go to Settings > Experimental > Entities and see entities created after you finalized filled forms. These entities will only exist until Collect goes out of memory. These experimental settings will not be included in the production build. This is mostly a tool for developers but some beta testers might find it fun to try! 
We considered using symbols but it didn't seem to us like there was a standard for them. What code did you try? Is there a standard that you're aware of? Or do you mean using an HTML entity like 😀 for 
?
Yes, you see where this is going! You will be able to have a form with a calculate that looks like if(${damaged}="true", "#ff0000", "#000000") and then map that to an entity property named marker-color. Then if the dataset is used for a select with map appearance in another form, each entity will have the appropriate color based on the ${damaged} field in the original form.