I would suggest getting regular trims to cut off as much of the damaged parts as possible. Maybe every 6-8 weeks?

I really don't know much about coloring/dyeing hair. Are you using the Aphogee stuff as a protein treatment? How does your hair feel after you do it? Lots of wavies use protein treatments but most people have to follow with a moisture rich conditioner to help restore the moisture balance. Lots of people like GVP conditioning balm (Sallys) but I really like Curl Junkie Curl Rehab (online).

What products do you use besides KCKT, KCCC and SN?

If your hair is really coarse, you'll want to stay away from lots of protein in your hair products.
Coarse texture, normal-high porosity, normal elasticity (Komaza Care), very weak waves
cleanser: Redken Fresh Curls Shampoo, CJ Daily Fix

rinse out: GVP Conditioning Balm, CJ Beauticurls, CJ Smoothing

jellies/creams: CR Curl Maker, KCCC
gels: CJ CQ, CJ Pattern Pusha, BRHG