What I hate in RPGs usually - not fun boss fights. They just load the boss with health points and make their attacks hurt you a lot. I know its easy and cheap to do it that way. But I like Dragon Ages Origins better in that regard, you can apply strategies in DAO based on the set up of your companions and your own class.
I remember the fight against the mage and his huge fire gollem pet - it was a LOT of fun. I played a guardian/tank. Gollem had a big fire AoE on him so you couldn't just tank and spank. I sent all my companions against the mage itself and lured the gollem aaway from the main group so that fire AoE wouldn't hurt them and I had some good fire resistant armor on. So while they were hitting the mage I tanked the gollem.
After mage died I've set the companions to range assist me and we downed them both on a first attempt. It was one of the most engaging and fun fights imho in DAO. Fun for me personally because I loved that it was possible to apply the strategy.
With this boss in Maxos temple I collected all the ingredients, read the book, got him into a human form. Then I killed him by using Jump Attack. It felt really stupid that I had to jump like a frog up and down until he died. If I didn't jump he used ranger skills and mage spells on me, he used fear and while feared just finished me with couple of fireballs or exploding arrow or whatever.
Even though I like DKS, boss fights are pretty stupid. A lot of HP and high dmg, thats it. Spam the potions and your most damaging attack, this tactic works on every boss. In some cases its better to run around the room and finish off the adds first.
Every boss that I had a problem with my solution was almost always - pet and/or jump strike. Thats the only thing I don't like in DKS. Also I become a bit bored right now. I just got my gate spawned into Hall, so I am close to the conclusion. I don't know if i want to do as many side quests as possible before I go in. I kinda want to get it over with and switch to Flames of Vengence already and roll a pure mage or something.
I play a berserker version of a warrior, dual-wield, battle rage is like lvl 11 nothing survives. Of course I get overwhelmed sometimes in flying fortresses but walls is your friend

. I am lvl 21, in Battle-Rage I kill lvl 26 in 3 attacks so its not too easy

. Flying fortresses are probably the most intense and fun battles in game. That is at lvl 20 against lvl 26-27 mobs.. lol

My alchemist can't make enough potions I eat through them very quick. Glad I have my workers to send harvest herbs for me.