Can marker symbols/text symbols be customized?

Another question: In unstructured FM, can marker symbols (text symbols) be customized and without having to use a Character style or a condition to assist with its visibility? For example, say I want to use the Comment marker in a particular way on a section heading, but the heading also has an Index maker symbol and a bunch of other markers. All the marker symbols look the same unless you apply a character tag to them, but for time management reasons, I want to avoid that step - I just want to be able to insert a marker that would automatically look different depending on the type that I select (for example, I was imagining that the ability to customize markers might be the same way that you can already customize Conditional Text markers [Edit Condition Tag], so why not marker tags?). If a section heading has a bunch of markers on it, it's difficult to visually distinguish them from one another and hypothetically, I don't have time to then select the marker to then apply a character tag to achieve that visibility. So I was wondering if there was a way to distinguish Index markers from Comment markers, for example (or, in another way, since they're text symbols, is there a way to customize text symbols?).

Additionally, is there a way to make marker text visible inline without having to open the dialog? For example, inline, similar to Word's hidden text setting.

Note, I'm NOT talking about editing the marker name/type (i.e., using Edit Custom Marker Type). I'm talking about the way the symbol displays on the page in View Text Symbols mode  (i.e., can the T symbol be customized and again, w/o having to apply a character tag).

I've searched in the Help, Reference page, and Preferences, and have right-clicked on the entry field in the Marker dialog, but haven't found anything (and although I like the unicode character options in the Marker dialog right-click menu, but don't think that answers the question). Plus searched through the forum on "marker" etc., but no dice.

Thanks.