If I may, I would like to make a few minor suggestions to the advent children theme.
The theme looks great, however the almost neon green does seem out of place. The green is much brighter than its surroundings which brings me to my next suggestion.
The wallpapers being used are fantastic, however, they seem a little washed out or dulled. Mabye if they were brought up to a higher resolution or brightened and made clearer, the pictures would stand out more and put out more eye candy in this theme.
You couldn't have made a better choice for the guide blade, well done. My only suggestion here is the "Materia 360". It blends in too much and kind of disapears in the color. If it were darkened or outlined a bit, it would be much easier to see.
My last suggestion would be the blade tabs. I love what you did with them, but again it's very hard to read the lettering. Of course we all know what blade we're on, but it just seems more polished if you had a box so to speak around the lettering that was a different color or texture that made the lettering more visible.
I am very happy with this theme, your doing great, thanks.
Can't wait for the panzer theme.