You're right, it's been suggested several times before. The basic response is that it's not going to get changed, because some people like it, so changing it would just leave the same situation. Some people would love the new animation, and some would dislike it and want it changed (back). So basically the work it took to change the animation would have 0 net effect on the amount of complaining done about the hasten animation.
I'd kill for a "aura toggle" for just about every power with a aura. Such as Integration (omg I have a radiating green power-plant in my chest!), Hasten, and so many more.
Personally, I don't need a aura to tell me I have them toggled on, as I've heard that was the general reason for toggles having special effects, besides the obvious "oohh pretty lights" art. Especially now considering defensive toggles don't detoggle when mez'd, only suppress, I know they're going to be on pretty much all the time unless my blue bar drops.
I don't know how much work it would take to do this, or if even possible, but it would mean a lot to me.
Also, I know I can adjust it to where I don't see *any* of the effects which would eliminate Hastens/Integrations/etc's effects but it would also reduce all others, which many I like.
But yeah, short of all that, I'm also not a fan of Hasten's aura. 
I guess that is true that no matter what change happens, someone will always be upset about it.
I think the best solution would be to implement something that asks you whether you want aa specific aura to show or not. Like a yes/no type thing in the enhancement window.
Eh, I don't know. They'll probably never take the time to do it. 
This has probably been suggested many times, but I would really love for them to tone down the bright yellow glow your hands get when you use hasten.
I'm not sure why our hands should be glowing when we use it, it just gets in the way. My main is a Night Widow, and when I use hasten I can't even see my claws... I'm sure Claws/* scrappers and stalkers are just as upset.
Really, I don't see any need for that huge glow, beside letting others know that you have hasten activated. All it does is get in the way of my toon half the time.