I got some of these runes when Yasuo was first released for experimentation... Not really much else use for them. However with Ashe's new re-work coming out removing crit chance by giving her increased damage based off her crit chance, I'm wondering how these runes will interact with her kit
They kinda explained that. Like, completely.
Ashe's basic attacks and abilities apply Frost to enemies damaged, slowing them by 5 / 11 / 17 / 23 / 29 / 35% for 2 seconds. Ashe's basic attacks against frosted units always critically strike, dealing 「 10% AD, plus an additional 1% AD for every 1% of her critical strike chance that is modified by 1% for every 1% of her bonus critical strike damage 」as bonus physical damage, but Ashe otherwise does not critically strike.
Until she has crit chance, it does nothing. However, once she has crit chance, it is the strongest multiplier in her passive.
Flat AD runes will be strongest in early level trading, crit chance runes are best for mid game, and Crit damage runes will give her immense late game damage (if you take Crit damage marks and quints and build a lot of in game crit chance (like double PD+IE) every single AA will deal around 1000 damage late game. She will be one of the highest damage late game ADCs in the game with the proper setup.
It does apply for her, precisely why they're nerfing her AS/Lvl to 3.33 instead of 4. Basically she will proc that mastery point every auto attack except the 1st.
Uhm..... 
+
+ ==All CC u need to do.
BTW the %runes affect items CC Damage as well... not just the passive. Furthermore the runes you refer to should be to boost the damage above... and not for early game pre-item builds...
