This was something i just noticed yesterday on a player who is a champion fighter. The improved critical note on character sheet vanishes at level 10 when additional Fighting style seems to over write it superior critical at level 15 will then show up. Also several of the additional fighting styles dont show up, its sort of hit and miss but i have seen defense and dueling as additional fighting styles not appearing on the sheet but additional fighting style is showing just not which one was chosen and what it actually is.