Not only are not all of those steps necessary, but some of them are out of order.
Wash, clay, two-step polish, then either sealant or wax. Sealant must go directly onto bare paint (so the glaze, if used, would be after the sealant, not before). You can certainly add wax on top of that if you wish but it is not necessary. If your car is a garage queen, you can skip the sealant and just go with wax. If it's a daily driver, I would go with the sealant since it lasts longer and has more durable protection from the elements.
If you are getting a dual action polisher like the porter cable 7424xp and want to get your black paint looking right, I recommend Adam's two-step polishing system as stated above. You can watch an instructional video about it (and all of Adam's products) on their YouTube channel, but below is the link to the video specifically about using the two-step polishes with the PC7424
As far as towels go, Adam's sells the softest, high-quality microfiber towels I have ever put my hands on, and with proper care they will last a long time.