Different symbols for bookmarks

at the moment when creating an own POI the only symbol is a star symbol. Is it possible to at least create a prohibition sign as alternative bookmark? I would like to use this as a marker for NOT use this road a 2nd time.
Thanks

I will review bookmark implementation in the future.
Then we can see what improvements are available.

Different symbols is complicated.
Different colors is more likely, also working with export / import.

Ok, I guess any symbol with red background color or filling would suit too.