I believe this is very easily accomplish with ViewCaptureToFile and PictureFrame command. You can capture the detail, and attached it as PictureFrame to the layout, You could also render, and attached the image to the Layout. That is all I can suggest.
Text height is the true height of the object (annotation scale off) or it is scaled to be exactly the print height in the details. (Annotation scale on). You get the choice in how you prefer to work and this is a per model setting…
As Dale said, it sounds like you need to spend some time looking at the layout feature together with annotation and details scaling, but specifically the info on annotations scale, this video.
My guess if you text is too small, that annotations scale is on, but the text height is very small. Increase the text height in object properties, and you should be good.
Please post your model if you continue to have problems.