The amount of scarring is proportional to the depth of the abrasion. Color is red orange in fresh rash, pink in healing/healed rash for the first several months gradually fading to white over 4-6months or a very pale pink. If the dermis is largely preserved the skin will be able to tan but there will always be a color differential. Scars also thin out with time so that exuberant red/pink scars over the course of a year will be smaller, paler and thinner. One exception is lower leg where intrinsic skin tension tends to enlarge scars that are full thickness (such as lacerations) for several weeks to a month. Roody is correct, scabs are not good, scarring is worse with scab formation (and abrasions are generally more painful when scabbed than when properly dressed and moist).
Steve