Be a thief
Isn't 5-forces fun? I think so. So what can we learn from this? For one, that it's important to consider strategy on multiple axes. How will a business deal with its suppliers, its customers, its competition?
Also, it is actually a weakness to be too vertically or horizontally integrated, as that creates a certain arrogance and/or passivity towards how you deal with these parties. New entrants will eventually come, and probably on a different axis all-together. Being too integrated, means that the business has many dependancies, which will make it all that more slower to react to changes.
What I think always pays off, is to be close to customers. By constantly adjusting your strategy, so that the value proposition for customers is increased and personalised for them, you ensure a certain loyalty (which gives you time to change) and you can sense it sooner when their attention drifts towards other types of products.
A final thought. Business is very much an art-form and in art there is one great saying: "Good artists copy, great artist steal." The copying refers to that everything has been done to a degree. People have sold computers, books, furniture, and those products are clearly fulfilling a demand, which, for now, continues to exist. Where people can innovate is in creating new combinations of things. In other words, if you copy a competitor's business-model, you gain only the part of the market that does not already get served by the existing business-model.
If instead you steal the good parts from other business models, and create your own combinations of these good things, you can create greater value-propositions for customers than already exist. This applies just as much to combinations of five forces, as it does for anything else.