QGIS rich multiline labels, with different fonts, with symbol inserted?

Question

This is now easy to make multiline label in QGIS, with concatenation in expressions.

I would like to know if it would be possible to have different fonts, one per line (or per item).

And to make the label richer, it it would be possible to insert - IN the label - some symbol, like arrows, SVG, etc.

Thanks a lot.

Cyril