Hi Scheb, it is a combination of all the factors you mentioned above.
A good shot of espresso or ristretto and then milk microfoamed and textured to give you that velvety smooth taste.
Making good coffee is an art form requiring fresh beans, a good grinder, tamping and dosing are crucial factors as well, brew temperature.
On occasions I use a full cream single origin milk from the SW of Perth and it makes heavenly long whites and capos.
Im sure you will get plenty of advice and encouragement from this forum from our enthusiastic and passionate CSers...............MERRY XMAS AND HAPPY COFFEE YEAR!!!!