<<Basically, needing a 46+ roll to ward them means an exercise in frustration of this like level creature. I get maybe it's just this creature, but I'm having to go down at least two levels to reliably ward things right now (warriors in the wolve's den). Any idea what I may be doing wrong, or can do differently?>
As Avaia said, arch wights aren't really the best prey for sorcerers. Besides their armor giving them a horrible CvA, they're magical creatures so they're going to have a higher TD then something nonmagical and you don't have enough mana yet to be hunting with 719 (which is more effective against magical critters then nonmagical ones). If they can be stunned with 706, you can hit them with that to hold them still long enough to use focused 710 on them safely, but it will be a headache getting a high enough end-roll to make 706 last long enough for 710's damage cycles to begin.
Don't worry too much about hunting critters exactly at your level. Sometimes those will be the best ones for you to be hunting, but more often you'd be better off hunting something +\- 2-3 levels. Heck, I've stuck with critters until they were 6 levels below me just because it was a fun area to hunt or they had really good loot. Unless you're trying to live in a town that's difficult to get to, like River's Rest or Zul, there's no reason not to pick and choose what you hunt.
If you're trying to hunt arch wights cause they have good loot, that's because they're generally hard to kill and most players avoid them. Critters in towns that are less populated then the big three (Vaalor, Ice Mule, and the Landing) will generally have better treasure then anything around the Landing and you can usually pick something better suited to your character. If you don't want something quite as isolated as River's Rest, you might try SolHaven or Teras... though it might be better to wait a few levels before tackling Teras.
Starchitin
A severed gnomish hand crawls in on its fingertips and makes a rude gesture before quickly decaying and rotting into dust. A gust of wind quickly scatters the dust.