Yeah, I tried those too with no luck. A lot of people said the reason they left the stances as a toggle & not as individual options was so that you couldn't create scripts to use all the special moves, or combos of special moves from the different stances (forward lunge immediately followed by DFA, etc.). But if someone really wanted to they could still create scripts to do exactly all of that.
For example, if you have a favorite stance that you always play with, you could create the keybinds to cycle the stances the number of times you need to get to the stance you want, do the special move, & then cycle the stances again to get you back to your original favorite stance.
This should give you an idea:
bind x "+saberAttackCycle; +forward; +moveup; +attack; +saberAttackCycle; +saberAttackCycle"
When playing in Blue, this will automatically change you to Yellow, do the Yellow DFA move, & switch you back to Blue again.
You can make keybinds for every special move, or combos, or combos with mixed stances, or anything else you can think of.
Now if you get that, this next item will blow you away! You don't really need to play in the same stance all the time to do these moves!
Let's say that you used the example above & created keybinds for keys Q-Y for the 3 special moves plus the 3 different backstab/slash moves, so that they all start & end (or stay) in Blue Stance. In the row below you can use keys A-H to bind the same moves but this time alter the number of "+saberAttackCycle" commands in each keybind so that they all start off & end in the Yellow Stance. And on the row under that you can use keys Z-N to do the same thing, but alter them so the moves start & end in the Red Stance.
This way you don't have to stay in one stance, you just use the row of keybinds that matches the stance you are currently in. If you happen to be in Yellow, use the middle row; or if you're in Red, use the bottom row, etc.
But remember that if you are pressing & holding down attack while trying to change stances, the stance will not change (even though the color on the HUD does) until you stop pressing attack. So the same would hold true for these binds, I think.