I agree that the heuristic is far from complete. I've been tempted to add to it many times, but for me, it starts to diminish its usefulness.
I'll use "my test" to indicate areas that might have less consideration. For example, solution design tends to get the most attention from founders. You have an idea and start to run with vision and possibilities.
But, as you noted, the attention given to economics may be lacking. This can help remind you to try to balance your planning.