Thank you Balsamiq for updating to 4.3.1 with new feature “Arrow”. This is REALLY nice. More of that.
One suggestion related to that: If you could add a button “set DEFAULT”, so that next time you use quickdraw the tool would draw with the parameter set in the arrow selected for default - you would at the same time, without doing anything, also have a quick draw for lines. AND double arrows. AND straight arrows as well as curved.
This could be as simple as storing default settings for each type in an SQLite file.
Mockup of idea: Button can be clicked when object type selected, and properties change. This will then be used for next (quick) draw of that object type.