One of the appealing features of Keyboard Maestro is quite "live" result display of action (when possible): very useful when learning and developing, specially regular expressions as in below Aqua (simple) action:
IMO, with regular expression, Search & Replace Variable action deserves "Live display" as Search Variable does and the space can be made easily available: it is up to the author
Tool tips display as you hover your mouse pointer over a fields to be revealed are also a nice alternatives or supplements…solving “live displays” truncation.
Tooltips cannot be live updated. At least, not code I ever tried made it work. I had to remove tooltips from the Modifiers/Weekday buttons because I could not live update them, so they could get out of sync with the state of the button.