There is essentially no difference between the two titles despite expanded options for item creation, a few new Force abilities and new "stances" to be used during combat. These things might look good listed beside marketing bullet points, but they're inconsequential.
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Calling a spade a spade, the game runs like garbage. For example, the framerate is absolutely atrocious. It's frequently possible to actually count frames of animation as the onscreen action grinds down to a crawl, and in countless places it actually halts—though I will say that it never actually crashed in the thirty-odd hours it took me to finish the light-side adventure. Small praise, indeed.
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Most of the beings on your team are dull and not very engaging any way you slice it—the notable exceptions being the humorous assassination droid HK-47 and Kreia, the main character's mentor. Kreia's role in particular is actually quite fascinating, but the rest of the time spent conversing with my rogues' gallery fell flat. The first game offered multiple character-specific sidequests and healthy dialogue trees for each of the crew, which are now largely missing. With KOTOR 2, it was much harder to get the same sense of depth. There are too many instances where the characters would either not respond or have nothing new to say unless I had rotated them into my party and increased influence with them. When I finally could get them to talk, I was often met with looping speeches that repeated nonsensically and eroded the sense that these party members were anything more than placeholders.​