Wow, for a guy making his own sigs now, amity's real nice to keep making you ones. 🙂
Your newer ones are doing stuff better. A suggestion though: Use smaller-sized sigs. There seems to be a decent amount of dead space in your current stuff, and making them smaller would focus your work more. The earlier Colossus one is a good example of less = more.
And I see you figured out the transparent layer stuff. Start doing that with aspects of your background now rather than just renders. You can create all kinds of fun layered, textured effects this way.