I run in standard HD resolution with a normal GUI scale.
This means my menus and tool bar etc are half normal size.
A lot of the text in the quest book is not easily legible if I use the Jaded mixpack texture pack. lower case Ls mostly disappear.
Then you should change the GUI-Size in the Options ;)
The tektite style font goes janky, if I remove Jaded's texture pack its fine. I run the gui a bit small so that F3 doesnt spam out most of the screen. There is something screwy with the special font used in the texture pack which doesnt resize properly.