What should I fight to get a good baseline so I can work on improvement?
Yes I would kick the sorc pulling low numbers you are there to dps not to heal. If the healer is messing up then they should kick him
Yeah, if DPS character is having to heal when you have a dedicated healer in the group, that's a problem. That being said though, I can't tell you how many pugs I've been in where somebody stands in some high-dmg AOE and then complains about heals.