It sounds like you guys had a real good time doing this.
And that's the best part.
As to your plan for improvement, probably the thing to practice the most is transitions - the time it takes to go from target to target.
While the draw and reload times can make a difference, you only do each once per course of fire in IDPA.
The time between good hits from target to target is more important, since you may be doing it up to nine times per stage.
Lock the doors, they're coming in the windows.