The Challenge Rating system in DnD/d20 is optimized for a party of four so that four should be an adequate number. It sure beats a party of 2 or 3. I just hope the difficulty value for this game, especially on the hard core DnD setting is actually hard unlike NWN 1, SoU, HotU, KotOR, and KotOR 2.
I don't see why Obsidian would want to do business with LA after they screwed them over with KotOR 2. Just let the series die. If Obsidian wants to do another Star Wars CRPG, plan it as a trilogy from the start. Let the player be able to use the same set of characters throughout all three games. Make the games long enough that the player can actually get attached to his or her character, then do the cliffhanger endings. It will have a far more dramatic effect.
The only real reason, at least for me, why the cliffhanger ending failed in KotOR 2 because in the end I felt nothing for my character. I didn't grow attach to him at all. Now if Bioware designed KotOR 1 that max level was 10th and KotOR 2 takes you to 15th to 18th, and you use Revan throughout both games the cliffhanger would have more effect.
Just my 2 scents worth on that.