4 and 5 seem hard. Consider the “Archipelago” idea. Also, this model assumes the idea is easily disproved/proved, and isn’t worth iterating on further.
(Rough) Contrasting model:
1) I want to make a [lightbulb] (before lightbulbs have been invented).
2) Come up with a design.
3) Test the design.
4) If it fails, go back to step 2, and start over, or refine the design, and go to step 3.
Repeat 100 times, or until you succeed.
5) If it works, come up with a snazzy name, and start a business.