Nice going there Rose....
I'll list them in the order which I think is best.
From best-worse(although imo they're all pretty good)
1- Nightgale Sig--> I like the Proportions of the person+the symbol, although the person could be made to stand out more and the symbol a bit less. 8/10
2- Your Kealix sig--> Editing wise this surpasses the Nightgale sig, but it's just not my sort of thing:D. 7.5/10
3- The Rogue sig--> It has a Murlock in, do I need to say more???....Actaully I do, the colour of the text in this suits the sig but you could've used different fonst of texts for both figures, The Murlock text doesn't suit it....it needs to be more.......epic:p 7/10
4- The Warrior sig--> it's a bit too bold for me(although I do like the colour combo) you could've tuned the colours down a bit. The fading in the bottom half of his leg is done nicely so 7/10
5-The Warlock Sig--> I like how everything looks as if it's coming out of the figure, however you could've done someting else with the edges such as a faded enlargement(if you don't understand me if not....you know who I am). 6.5/10
Lastly the Undead sig...The figure itself looks good, but you could've done something to that massive gap on the left and you could've made the grey a bit lighter.
Now the Wallpaper....I Like it, 9/10 for that-->nothing is perfect :D