I'm glad to see that I'm not the only one who finds the data field invasive and difficult. I may be fairly new to IronCAD but I've been a 3d designer for 30-years so I do know my way around complex software.
I think that providing some configuration parameters would help. Just being able offset the data field by some amount would help. You could choose to offset it (+) and/or (-) a number of pixels to send it diagonally up between the two axis, or whatever worked for you workflow. As powerful as the feature is, I agree, having to make many multiple clicks to get it to behave is inefficient. Reducing the font size as Cameron suggested is a start and is helpful, but even with the character height smaller, the field's boundary is still larger and invasive.
In reality, the sizebox text field annoyances are not a deal breaker. But, it's just a feature that you handle so frequently that a little bit of redesign would make things nicer and even faster. And being able to model "fast" is what makes IronCAD so powerful.