Knights of the Old Republic II is infinitely better than Knights of the Old Republic 1, which is just a collection of mostly bland stock characters who fall firmly into typical Star Wars archetypes (apart from Bastila. Bastila is the only interesting character) hanging out on boring stock Star Wars worlds and it has a boring villain with an uninspired design. KotOR II features far superior writing, a more nuanced story that deconstructs Star Wars mythos and the simplistic concept of the Light Side and Dark Side and has unique feeling villains with great designs and multiple interesting twists.
On a similar note, Dragon Age 2 is the best Dragon Age game. It has the most interesting partymembers, the most tricky and interesting moral decisions, a bunch of twists at the end of Act 2 that had my mouth hanging agape in shock and oh my god, the surprise betrayal at the end will really catch you off-guard. The characters in DAI are like author's pet cartoons or Tumblr OCs by comparison, especially Varric, who is horribly out of character like late GoT series Tyrion, and DAO, feels stodgy and hard to get through. DA2 is the perfect Dragon Age to me. It's stylistically confident, punchily written and well-paced.