Why is "color" not available as a key frame tween choice?

Question

There are choices for position, scale, skew, rotation and all. One of the most common things I do is tween alpha for fade ins and outs. Why is this choice greyed out?
Of course I know I can just select all, but then what's the point in listing all the properties separately for tweens?

Answer 1

I think you can simplify the new tween a bit.
For (2) in new motion tween, you can set where you want the last keyframe to be, just like you do with classic tweens - it doesn't need to extend to the end of the entire animation. Create the static span of frames first, then apply the motion tween. This should shorten some steps for sure.
For (3) you do not need to go to the motion editor and then go back to the Property inspector - you can apply Alpha just like you would with classic tweens using the Property inspector (and this can even be more efficient than classic tweens, depending on your animation and how you're creating keyframes, since you only need to apply it once). You don't need to flip between Motion Editor and PI as in your steps.
Step (4) is unnecessary - just change the alpha in the PI (or Motion Editor if you happen to be there). It automatically inserts the keyframe for you.
But it actually sounds like you might be doing a fade in and fade out. This would have fewer steps for new tweens, because you just create a single tween span, move the playhead and change Alpha in the PI (auto-creating keyframes), and you're done. And an added benefit if you need to retime it, because you can then stretch this span to modify the length without ruining any keyframes.
Perhaps (7) I could help with a bit more so you can avoid splitting the motion so much. Sounds like you are easing between keyframes and splitting the span to do so? There are two options for easing the alpha: you can just change the curves in the Motion Editor, or you can use a custom ease. The easiest one would be making curves in the motion editor (and this is probably much quicker than using the Ease setting for classic tweens). Select your tween, and find the Alpha property in the Motion Editor. Now you just need to modify the curve in that property to control the animation, which essentally eases the animation (ie: if you have a beginning, middle and end keyframe to fade from 0 to 100 and back to 0, right click all three and choose "smooth point" - the default might be what you're after).
Perhaps not the case here, but for what it's worth, when you are easing between keyframes for position (spatial properties) you probably want to use a custom ease. I have some steps here: http://flashthusiast.com/2008/11/20/flash-cs4-how-to-ease-between-keyframes-using-new-moti on-tweens/. (We are working at improving this workflow in general for easing between keyframes).
Does that help?  I can elaborate wherever needed