There's still quite a lot of Indoril Guards wearing a mix of vanilla Chitin and Chev-Aram pieces, and as far as I can tell, it's not intended - it's just that nobody updated the armor of those NPCs once the rest of the Chev-Aram set was added to Tamriel_Data.

Also, almost every Indoril Guard has one leveled list item T_Mw_Random_ArmorIndGuard in their inventory, which contains only one item - the Chitin Cuirass. This is also definitely not needed, or desired, considering the guard also have the correct Chev-Aram Cuirass.