LOL! Redcliffe is a saturday night pub fight in comparison to the rest of the game!
in terms of actual duration, redcliffe is probable the longest single battle... which is what makes it so taxing for wrong built & low-level parties that is unaware they need a large stock o' potions. in every other portion o' the game you may inch towards daylight... fight & rest, fight & rest. heck, those lyrium veins that show up in various places significantly ameliorate the player's need for potions as the mage types may re-charge on-the-fly and then heal party or smote foes. no such option is available in redcliffe. also, aristes did dahlish first, if we recall correct... and then the mage tower.
HA! Good Fun!
A low level melee party that goes to Redcliffe first (gee, thanks Alistair) will get zombie-lynched by hordes of undead mobs with no daylight on the horizon. That's what happened on my first playthrough & 'twas a nightmare. However, since then, my fireball toting mage makes light work of them without even needing to use health potion.