I'm a retired Architect who uses QCAD more as a hobby but I do have a few ideas that could make QCAD more common in a professional office.
1. Feet and inches- The U.S. never really adopted the metric system, and with RibbonSoft being based in Europe it appears that the programmers never fully have come to understand how we communicate feet and inches.
As an Architect I say a room is 32'-6 1/2" X 40'-5", to draw this room in QCAD I either have to know off the top of my head how many inches are in 32 feet or convert it before I can enter it. ex. 32' = 384" + 6.5" = 390.5" and then enter that. It would be nicer if I could just enter 32'6.5 as is done in AutoCad.
2. This one applies across the board, all disciplines and nations. In the CAD tools, could the edit features be in there own toolbar? I personally am constately drawing lines and then trimming, extending, rounding, etc. and finding myself having to back out of the line command and then entering the edit command, back and forth, back and forth, it really slows one down.
3. Could some features be added to layers? These include Layer Set (LS) and Layer Change (LC). Ex. in my drawing to change my current layer to one I want to draw my next line in I type LS and then select the line in the drawing whose layer I want. For Layer Change I type LC then select a line and it changes it to my current layer.
I know there are ways to do each of these things without changing the programing but I merely suggest them as a way to make drafting more efficient and streamlined.