This is still a great guide, I don't like moz tool, find it pretty unreliable and sometimes make no sense, but the steps you show here a good foundation to not dive in head first before seeing that the competition is just too big, plan carefully and analyse if you will lose too much in order to have a ROI. It is always an estimation of course because you never control anything with seo, it's like a chess game where you put odds in your favour.