Oh, if you don't have Wynne you're pretty much completely fucked if you're not mage yourself or have specced Morrigan towards healing. You need a healer. Or a ton of potions, so a good herbalist could get you through the game, but potions can't be used when a character is held by an ogre or dragon, knocked down, paralyzed, frosted, or in any of the other situations where you really need healing fast. Oh and by the way, if a character gets curse of mortality'd, it's night night if you don't have a templar around to dispel it.
That specific thing I'd solve by having a sneaking rouge go ahead of the party and open the door, and try to bait out the enemies.
One of the big problems with that game for me is that some builds are just straight up shit - specifically two handled fighters. Since two of the characters come specced towards that - Oghren and Sten - they're pretty much a bad choice to bring to a fight. They have decent damage output, but not near the longevity they need when standing in the front and getting punched by ogres. You need a shield warrior for tanking, a mage for teh heals and crowd control and a rogue for lockpicking and trap stuff, so the two handled warrior can be a good choice for the fourth member of the party, but if your main character isn't one of those three first classes, Oghren and Sten simply end up with no utility.
