Im a huge fan of beard oil and recommend it to everyone with facial hair of all lengths. The essential oils in our beard oil can make your beard hair soft and your skin healthy, making it feel more comfortable on your face and less itchy or irritated. I recommend applying a generous amount in the morning and a small amount at night. Whatever is left over on your hand apply to any area of skin that is exposed to the world. Beard oil should have a nice light smell and not be overpowering so its not overwhelming. As a barber I always remove the hair on a clients neck creating a sharp line, not to high up or low. My rue of thumb is when you look in the mirror the line should just not be visible. its important to remove it because can be itchy and unattractive. I leave the cheek area as natural as possible removing any hair on or above the cheek bone.
Hair coarseness is a function of the thickness of each individual shaft of hair. Beard hairs are coarser than scalp hairs because they are individually thicker than your head hairs. One of the main things that influences hair thickness is the size of the dermal papilla, the space the root of the hair shaft sits in at the base of the follicle. Dermal papilla size is characterized both in terms of the space afforded within the dermal (skin) matrix and the number of cells at the dermal papilla.
The dermal papilla in male beard hair follicles is around 4 times the size of dermal papilla in male scalp follicles. So you can expect that beard hairs are thicker than scalp hairs.