I seriously doubt Sid will return, I read some rumours but nothing definitive. Honestly I don't think anyone would care, I know I wouldn't. He's old washed up and pretty much an idiot (you should see him on the WWF's Funniest Moments video--he's doing a live promo, screws it up and asks JR can he do it again. JR, looking astonished, says 'This is live, Pal.'And we thought Kennedy was a tool).
WWE have enough big names right now to do great things, they just need to get some good storylines, matches set up for Mania, not including HHH/Orton.
Kurt Angle was not overrated imo, he was a great wrestler and had great promo skills, I remember when he and Benoit were a tag team, some hilarious skits between the two. Him and Eddie (descansa en paz, amigo. Viva La Raza!) had a great rivalry too. I was disappointed when he went to TNA, mainly because I thought he should have taken a good while off to rest and get his body healed. I don't watch TNA, though I've seen some of the clips. I personally think he's wasted there, as is everyone else. (except maybe Jay Reso, WWE could have and still could do great things with him).