Ritardando continuation line terminator

Is there a way to have a hook on the end of a rit. line?

And can you change the text font?

You can change the font at Library > Font Styles > Gradual Tempo Text Font. Note that will change ALL gradual tempo text.

Don’t know of a way to add a hook.

Kind of clunky, but you could hide the rit. line then add a regular line. You’d have to align them in Engrave mode.