The Ziggler and Sheamus sigs look really similar, aside from the fractal highlights in the background of the Sheamus sig which look cool (they flow great with the render) but take away from the background itself.
Your two best works are Rhodes & James Storm imo. The Rhodes sig I like because it's so unique and the text is absolutely PERFECT. The Storm sig I like because of how much depth there is and again, great text. The depth in the Storm sig blows me away, though. Even the text looks like it's popping off the screen, it looks great. High Pass is a miracle worker, right?!
The Punk sig looks like it has potential. Maybe try using some filters on the background (spatter, sprayed strokes, ripple, ocean ripple, glass, etc) so that it doesn't look EXACTLY like a duped render layer. Unless that's what you were going for, but the big white chunks in the bottom left and directly to the main render's right look pretty bad. That, and it looks like the main render has a bad black outer glow or drop shadow that just does not work at all. Again, though, phenomenal text work - that's clearly your strong point and it's usually one of the most difficult elements for digital artists of any kind to master. Sometimes I'm working on text that, in my head, looks awesome, and then I finish, thinking "FUCK YEAH THIS IS EPIC," and then I sit back, look at the image and think "fuck, this looks like a buffalo took a wet shit on my sig. *deletes text completely* Let's try this again." - that exact process happened on my newest Punk splash. I tried adding, in big, cutesy Web 2.0 stylized font, "THE VOICE OF THE INTERNET MARKS" at the bottom (to make it look like he was almost sitting on the text) and it just turned out horrible. Needless to say, I left that text out and opted for the "Shove your borders up your ass" above his head.
Your font work is great and your background work is inconsistent, but when it's good, it's great. I'd say try doing a few more manips so you don't have to worry about making a background from scratch - the Rhodes sig is your best work imo and that's a manip. Stick to your strong suit, right? =)