Wargs can be a bit of a jack of all trade class. I would describe them as a primary dpser and secondary scout/debuffer.
Shadow stance gives us great dps, but we are quite squishy. Flayer stance gives us a bit more tankiness (although not that much) and a bit of a buff to our debuffing.
Warg's CC consists of sudden pounce (pounce from stealth), crippling bite/pounce combination (chance for knockdown), and tendon shred. So not really much CC, but it's enough.
And yes, if the raid leader is smart, they will have warg scouts out following or finding the freep raid(s). I absolutely love being the scout and it's even better now that there is no infamy max range. So we can be out scouting and not missing out on any kills.
I highly recommend it. Here are some resources about wargs in particular: