There are a lot of viable scarfers out there...But what's faster than it, it outspeed likes 95% of the unboosted metagame...
Talking about ghost type, I even like gastly more than abra. It has better typing, access to destiny bond(free kill), better moves in general and an immunity(levitate). Abra may have better stats and access to psyshock (if you want to wreck special walls), but imo gastly is better.you do realize abra runs shadow ball.