sandfraeulein

With some options for "Underline” perhaps in a year?
 
In the meantime: Do it in an diagramming software and import the framed text into AD.

I'm in the same boat, sandfraulein. With Illustrator you can have text inside a frame, then specify the distance from the text to each edge as well as colour the stroke/fill if desired. Having to draw a border around every single box not only takes more time, it also does indeed introduce the strong possibility of inaccuracies occurring. 
 
I think that a good workaround might be to draw a rectangle (or other desired shape), then to to Layer --> Convert to text frame, and add type. Controlling distance from the edges of the frame can be done in the Paragraph palette. I just tried this out, and it falls apart unfortunately, because it won't let you add a stroke to the frame, only the text. At least doing it this way you'd still have a frame to snap to, which would solve the inaccuracy problem. This really needs to happen - might be worth a post in the feature request section.

There’s a simple way, sandfräulein:
Create an array of strokes, for example, by drawing one stroke, adjusting its parameters, duplicating the stroke to another place (Command + Drag), and immediately hitting Command + J afterwards, in order to duplicate it as many times as you want. Place your shape on top of the strokes. Select all strokes and clip them to the shape by making them a child of the shape in the layers list. Of course you can choose a different colour for your shape or make it even completely transparent. A video about the clipping and masking capabilities of Affinity Designer can be found here:
 
https://forum.affinity.serif.com/index.php?/topic/4069-layer-clipping-vs-layer-masking/?p=16825
 
But you can also use a bitmap fill, if you want to have raster elements in your drawing … just ask, if you want to have more information about this … there are also video tutorials on Affinity’s Vimeo page …
 
Hope that helps …  :)
Alex

Hatching.afdesign

Dear Alex,
This is very helpful :) .
Thank you very much!
sandfraeulein