All of these are pretty important, but way up there is the grind. Why? Mainly because of brew time. A coarse grind is better for French Press and a fine grind is best for espresso, although opinions differ!
A fine grind will work as well as any but you'll find debris in your cup if you don't let the grounds settle before drinking.
What's the secret? Consistency. I say that because you'll know what you like best. No one can tell you that piece of info. What you will like even better is a reliable grind that you can accomodate according to your brew method, whether that be drip, moka, espresso, even a pot over a campfire.
I began enjoying coffee the way most of us did. I drank coffee made with preground coffee in a stove top percolator. It was years before I tried espresso. It's a lot like listening to music. You're happy with scratchy recordings played over the radio in your old car until you hear stereo. The plot thickens. Have you read the Starbucks coffee descriptions that say certain varieties taste like chocolate? These subtle tastes become apparent as your palate matures. Bottom line: you know what you like. It may be instant coffee! It may vary depending on whether you're climbing your favorite mountain peak or sitting in the local cafe.
The point is that you're in control of the way your coffee is prepared. It's nice because it's simple.
I love my Hario hand grinder because working that grinder by hand is a nice way to start the day.
It also will grind my coffee in a consistent, fine way that is as good if not better than the most expensive electro mechanical machine. The star washer in the photo above is how the coarseness of the grind is adjusted. But, it takes a few minutes to grind enough for a couple of espressos. I wouldn't want to depend on the hand grinder with a family of thirsty people waiting!
What do you think? What's your favorite grinder for brews from espresso to drip? The nice thing about making a good cuppa joe is that it's within most everyone's reach to go from simple to elaborate and wind up with just what you like the best. Enjoy!