I've treated KP professionally, and I guarantee that these steps are more effective than any single spa treatment. So take charge of your KP and reduce it using these easy, effective techniques!
BHA body treatment I used: Paula's Choice RESIST Weightless Body Treatment with 2% BHA -- This stuff is absolutely amazing! I have been using it regularly for a while now, and I 100% recommend it.
My PC refer-a-friend link, for $10 off your first order: http://goo.gl/nr2GMb
(This is part of PC's referral program that is open to everyone! I will receive $10 in store credit, but I do not receive any payment from PC for recommending their products.)
Re: KP on the face and neck, skin is skin. If it's the face and neck, you still exfoliate and moisturize, just use appropriate products for the area instead of shaving and using a body-specific product. You can gently use the exfoliating gloves with your facial cleanser over the affected areas, and there are plenty of salicylic products for the face. Don't overthink it!
Other BHA body treatments exist, I just haven't tried them. Just remember, fragrance (including essential oils) and (bad) alcohol free! See my Good vs. Bad Alcohols video for more on alcohols.
Bad alcohols: SD Alcohol, Alcohol denat., Denatured Alcohol, Isopropyl Alcohol, Ethyl Alcohol, or just Alcohol, Ethanol, Methanol, and Benzyl Alcohol (when high in ingredient list, to be avoided altogether when skin is dry, problematic or sensitized). These do not belong on your skin!
Keratosis pilaris can go into remission with consistent care, so stick with it!