I prefer party based RPGs, but regardless I'd like the kind of dialogue options that allow you to create a personality for your character (As with PS:T) and for the dialogue choices you make to have real repercussions within the story.
A compelling story always beats an excuse to run around hitting things.
Romance possibilities are always good. Unless they are like Baldur's Gate 2, where it's a choice of bad, really bad, or worse <img src="/ubbthreads/images/graemlins/biggrin.gif" alt="" />
In general, the closer to the way PS:T works any RPG gets, the more I like it in terms of story, characterisation & dialogue options.
Diablo 2 is still the gold standard for single character combat and character power-ups, though. I know it's old now, but in terms of balancing the character types and overall challenge (Hard but fair) it has yet to be equalled, let alone bettered.
And definitely not turn based. At all. Ever. (Sorry Alrik <img src="/ubbthreads/images/graemlins/biggrin.gif" alt="" />) Edit:
I like these suggestions of D's too:
--Multiple Solutions/Pathways to Quests and the Main Quest Iteself
Multiple solutions to main quests, side quests, and to the main quest's ending a la NWN2 or PS:T, where some are good, evil, neutral, and even peaceful non-combat solutions.
--Game Can Still Continue After Finishing The Main Quest
After we finish the main quest, it'd be nice if we can keep playing in the same game world; especially if there's some quests I'd like to finish or actually do, once I finish the main quest
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