I used to ski Dynafit skis. I have a pair of their approach skis (the 130 cm) which are OK but are BAD for downhill control with a heavy pack and a pair of Carve Lites which have since been replaced by the similar-weight carbon-hybrid skis.
I now ski on Goode Carbon 82's. They are about as narrow as you can go for deep backcountry powder with a heavy pack. I have Dynafit Comfort bindings on them and ski in the Dynafit Race Pro boot.
Now, I see your criteria and your desire to "tour".
I think a touring setup is fine, but there's not a lot of touring to be had in the "Sierras" if you really are going up there for a mountain traverse, and I think if you think you won't encounter steeps you'll be underestimating the potential for routes there and probably, limiting yourself to the valleys.
An AT setup will at least buy you the ability to more safely get down mountainous terrain with a decent sized pack.
It's a ton of fun, too.
I think the only change I'd make to my current set up is to move to a slightly fatter ski. The 82's are a bit thin for the deep powder here in the Rockies. Since the Sierras are predominantly a coastal range, they would be fine.
Goode skis are expensive, but there has been some really good deals on them at eBay. I've seen them go for less than half their retail price.