...Shadaloo Approved, but I friggin' hate her online!!! She is the bane of my Seigfried's existence! 
Awesome sprite though. 
Dude I kno what you mean. Since Soul Edge this has been an issue but I have long found out a way to counter this whether your Seigfried or Taki etc....
Seigfriend's weakness is fighting up close, for he fights better with having some kind of distance. As the games progress in the series, they gave him and nightmare more moves to help with this problem if your put in an up close situation with someone else. But if you handle Siegfried like some of the very good siegfriend players then fighting people like taki shouldnt be a problem. Don't forget you can grab, and also his punches and kicks. Most people forget that he has that while fighting someone up close.
Taki and etc have fast attacks and are best used up close and are force to be very offensive fighters and yet their defense is not the best, they have very good evasive skills (FLips and what not) But their weakness still is fighting from a distance as they have to get in close to do damage. And this is why more of a reason why as a Siegfried player, you should take advantage of that and keep them away as much as you can.
Cervantes used to give me a problem as a Siegfried player, but I figured out how he works. Everyone in the game has a weakness or some one that can counter them, but its all about you knowing what moves to do to counter react to them.
Cinco de Mayo