I liked the ending. If a sequel is planned anyway (as in this case) you might as well have a cliffhanger ending as a fake happy ending, and then come up with a pretense to undo all the stuff you though you finished in the previous game. It's fairly cliché to start a sequel with an evil apprentice of the former badguy, a cult forming to resurrect him/her, or a revelation that they were just working for an even bigger badguy, etc.
It's not like there wasn't any hint of the ending (Damian was leaving you alive for something). There was discussion of the game during development about
moral dilemmas, and designing quests so there wasn't necessarily the classical good and evil choices, just choices and consequences. While the actual quest design kind of fell short of theory (theory not being restricted by time or resources), the plot/ending certainly held true to those design principles.
In any case, you can continue with your dragon knight in the
add-on (once it is released), so the ending is not the end of the character.
Ending........What does the ending tell us? *spoilers*
