Today, a turn after I got my Warlord's Stables built, I finally got to try out one of those Scythian Noble Archers. And, really, I was blown away!
Compared to the basic Scythian Horse Archers and their toy-like weapons, these nobles can actually take out a reasonable amount of infantry per volley!
In fact, my 3-bronze chevron Noble Archers took on a Rebel army of 3 Thracian Mercenaries and 1 Scythian Horse Archers in a Hard battle and won! I only lost 9 guys due to being surrounded by the Thracians. The arrows from the enemy HA did not even kill one guy!
Also, I learned to love the Cantabrian Circle, due to the buggy nuisance of HA units taking forever to fire all at once (the first volley that they should fire doesn't, with only the sound and firing animation being available!). Sure, the circle tires my nobles out, but read this: somehow units seem more prone to gaining experience when they kill enemies at Tired to Exhausted status!
Maybe I am crazy, but I think it's worth it for someone to test this out for themselves.