Personally, I would say that
!() is the best solution as it already is a media embedding, on the other hand, for backend rendering of markdown this will hurt rendering time a lot as they have to check source type for
audio/mp3 to determine the source type which is 900ms slower than just a normal embed. So 3 simple images will add a time of 2700ms while the standard
!() only use 300ms (100ms/image).
Tested in PHP 7.3
I don’t like the idea of adding new syntax but I have to admit that
@() isn’t a bad idea