On the bigger swimbaits I only use garlic. I don't use it as a fish attractant but to cover up any unwanted scents that may be on the bait. I always thought garlic was used for catfish but it has proven it's self over and over.
As far as soft plastics I started out using Hot Sauce gel but have since switched over to Smelly Jelly. This is on the rare occasion that I put some scent on. 90% of the time I fish the plastics right out of the bag.