To make Design Library Items as accessible as possible to everyone, using custom CSS isn’t something I would want to add for regularly used properties.
Some available properties are restricted as well.
I think this topic should finally be addressed.
Also:
For a full no-code approach, this is required as well.
Ability to add a website link to give the authors some credits for their efforts. This could motivate more people to add their stuff. Also, people could reach out via contact info if there are issues or questions regarding a certain design.
Ability to add a link to each library item, in case the author wants to add some notes or even documentation, video, etc. I generally like to create interactive designs which are above average complex and the average user couldn’t do anything without some additional hints.
Ability to filter by author.