1st sig :
text needs work,change the border,resize/change font of the text use chinese fonts,bg is almost saturated,no blending between render and the bg,needs more depth
2nd sig:
hard to recognize whats in the sig , ur like adding cartoon to graphic reality ( i meant the render) ,so ud add more blending and lightning to the render,and blend it,the background isnt interfacing with the render,so try to use another bg,or blend the render in it,needs more depth,lightning and text improvmnt,try adding border
3rd sig:
Same as above
4th sig:
render isnt blended at all,needs coloring work,and border is bad not matching the sig style make it normal border and the text needs better placemnt/font/blending in the sig,try not saturating the sig , and lessent the filters used in it,needs more depth in it
5th sig:
same as above ,adding overblurred
6th sig:
lessen the filters and as above,needs more effex and depth
7th sig:
same as above,lessen the brush strokes,one of ur best
8th sig:
i dunt understand whats going on in the sig but same as the above
9th sig:
depth,coloring,monotoned, same as above
10th sig:
best of ur's,text improve,and change the placmnt ,try using simple fonts like Arial
11th & 12th sig:
parts overcontrasted and needs more blending not just erasing the bg or parts of the render,try smudging it,and adding more effx
overall:
try reading more and more tuts.just take some ideas from here and there
and ud be better in faster motion

work on:
-coloring
-depth
-effx
-text plcmnt/font/style
kiu m8