I agree with Paillo that the pine tar scent fades .... no .... it mellows .... over time. It never really goes away and remains quite distinct. If you basically like the scent of the particular pine tar you are using, there's nothing wrong with just using it "au natural".
If you don't like it so much, you need to realize it won't ever really go away and there's no "masking" the scent. But you can modify the scent if you're willing to experiment a bit.
I have used a lavender, cedarwood, and rosemary EO mixture in one batch made with Bickmore pine tar. At first the EOs were completely overwhelmed by the pine tar, so I thought the added EOs were a waste of time and money. The soap is 5 months old now, and I can finally smell a gentle spicy, woodsy overlay from the EOs. It's a pleasant addition to the overall fragrance.
I made another batch with Auson brand pine tar and did not add any extra scent. The Auson product is more "smoky fire" smell like you get when camping or having a bonfire. The Bickmore has more of a "burned rubber" smell to me -- not so nice. In any case, I am actually liking the "unscented" Auson batch and I'd make it again without scent. The Bickmore ... well, I think added scent will be a good idea for that pine tar.