What else do I need to add the above kit?
probably just some applicator pads, you might have got them with the kit, i like to use a separate microfibre for each product, so you might want a few more of them. you'll want a
tyre dresser for the wheels too.
what you using to dry your car? i'd recommend the megs water magnet or the sonus der wunder drying towel (the sonus is better IMO)
MER is good but old school, and can be hard to remove and cakes, megs stage 2 polish is good and produces a nice shine.
what you can do is add some MER to your shampoo