[Caden]

I am curious as to how you made a spreadsheet, because I wouldn't have expected you to know how much strength a character has endgame and how to calculate that in. I would factor in 30 strength. Which would add a bonus 10 damage to each hand.

I should point out that the Firkrann crystal does ion damage. Ion damage only effects droids. So your math will only count towards droid enemies and not people or animals. So instead of using the Firkrann crystal in your spreadsheet, you might want to use the Sigil or Opila crystals.

My math would look something like this:
Double-Blade with Solari/Upari
Flurry = 173.25
Power Attack = 178.6
2 Single-Blades with Solari/Opila and Opila/Upari
Critical Strike = 177.8

And those would be the best numbers for each attack feature, before calculating Sneak Attack. I'm not sure why your math says that a short blade in the off-hand provides the best damage output. (Edit: I think it is because you are saying that AB increases your damage.)

With level 4 Sneak Attack, the numbers would look like this:
Flurry = 243.25
Power Attack = 234.6
Critical Strike = 233.8

Keep in mind that this is high end-game damage and doesn't include mid-game or early-game fighting. In order for Flurry to reach these high numbers at the end of the game, it requires that you focus on strength and neglect your other stats, as well as, being lightside to use the Solari crystal, and have Sneak Attack. Even with Sneak Attack, the mid-game numbers would still put Power Attack as more damaging than Flurry.

I know the numbers above say that with Sneak attack, Flurry is more damaging than Critical Strike, but those numbers require that the enemy be stunned at all times so that each of your 5 hits with Flurry will activate Sneak Attack. The truth is that a person using Critical Strike will keep an enemy stunned more often and will be getting more Sneak Attacks off. So with Sneak Attack, Critical Strike is more damaging than Flurry, despite the above numbers.

And, when you think about it, a person who uses Flurry and Power Attack won't really have a method of stunning the enemy early and mid-game. So the bonus damage from Sneak Attack shouldn't even be counted at those points. At the second half of the game you can start using force powers to stun some enemies, but even then, Critical Strike would be a more reliable way of keeping the enemy stunned. This is especially true against bosses who will be resisting any stun from force powers, but will be vulnerable to stuns from Critical Strike.