Here are some cool stepmania 3.9 compatible mods for the default theme.

Speed=14
SpeedDefault=mod,1x
Speed,1=mod,1x;name,x1
Speed,2=mod,1.5x;name,x1
Speed,3=mod,2x;name,x1
Speed,4=mod,2.5x;name,x1
Speed,5=mod,3x;name,x1
Speed,6=mod,3.5x;name,x1
Speed,7=mod,4x;name,x1
Speed,8=mod,4.5x;name,x1
Speed,9=mod,5x;name,x1
Speed,10=mod,5.5x;name,x1
Speed,11=mod,6x;name,x1
Speed,12=mod,C643;name,x1
Speed,13=mod,C682;name,x1
Speed,14=mod,C753;name,x1

Accel=6;
AccelDefault=mod,no boost,no brake,no wave,no expand,no boomerang
Accel,1=name,Off
Accel,2=mod,boost;name,Boost
Accel,3=mod,brake;name,Brake
Accel,4=mod,wave;name,Wave
Accel,5=mod,expand;name,Expand
Accel,6=mod,boomerang;name,Boomerang

Effect=26
EffectDefault=mod,no drunk,no dizzy,no mini,no flip,no tornado,no tipsy
Effect,1=name,Off
Effect,2=mod,drunk;name,Drunk
Effect,3=mod,500% drunk;name,Drunk
Effect,4=mod,dizzy;name,Dizzy
Effect,5=mod,5000% dizzy;name,Dizzy
Effect,6=mod,628% dizzy;name,Dizzy
Effect,7=mod,5000% dizzy;name,Dizzy
Effect,8=mod,65% mini;name,Mini
Effect,9=mod,40% mini;name,Mini
Effect,10=mod,57% mini;name,Mini
Effect,11=mod 64% mini;name,Mini
Effect,12=mod,80% mini;name,Mini
Effect,13=mod,600% mini;name,Mini
Effect,14=mod,flip;name,Flip
Effect,15=mod,50% flip;name,Flip
Effect,16=mod,tornado;name,Tornado
Effect,17=mod,21% tornado;name,Tornado
Effect,18=mod,22% tornado,6280% Dizzy;name,Tornado
Effect,19=mod,31% tornado,6280% Dizzy;name,Tornado
Effect,20=mod,500% tornado;name,Tornado
Effect,21=mod,200% tipsy;name,Tipsy
Effect,22=mod,2000% tipsy;name,Tipsy
Effect,23=mod,6280% dizzy;name,Dizzy
Effect,24=mod,2500% wave,100% drift,500% bumpy;name,Dizzy
Effect,25=mod,193.5% Mini;name,Mini
Effect,26=mod,2000% Mini;name,Mini


Appearance=8;
AppearanceDefault=mod,no hidden,no sudden,no stealth,no blink,no randomvanish
Appearance,1=name,Visible
Appearance,2=mod,hidden;name,Hidden
Appearance,3=mod,sudden;name,Sudden
Appearance,4=mod,stealth;name,Stealth
Appearance,5=mod,50% stealth;name,Stealth
Appearance,6=mod,95% stealth;name,Stealth
Appearance,7=mod,blink;name,Blink
Appearance,8=mod,randomvanish;name,R.Vanish

Turn=6;
TurnDefault=mod,no turn
Turn,1=name,Off
Turn,2=mod,mirror;name,Mirror
Turn,3=mod,left;name,Left
Turn,4=mod,right;name,Right
Turn,5=mod,shuffle;name,Shuffle
Turn,6=mod,supershuffle;name,SuperShuffle

Insert=8;
InsertDefault=mod,no little,no wide,no big,no quick,no skippy,no echo,no stomp
Insert,1=name,Off
Insert,2=mod,little;name,Little
Insert,3=mod,wide;name,Wide
Insert,4=mod,big;name,Big
Insert,5=mod,quick;name,Quick
Insert,6=mod,skippy;name,Skippy
Insert,7=mod,echo;name,Echo
Insert,8=mod,stomp;name,Stomp

Scroll=8;
ScrollDefault=mod,no reverse,no split,no alternate,no cross
Scroll,1=name,Standard
Scroll,2=mod,reverse;name,Reverse
Scroll,3=mod,250% reverse;name,Reverse
Scroll,4=mod,176% reverse;name,Reverse
Scroll,5=mod,400% reverse;name,Reverse
Scroll,6=mod,split;name,Split
Scroll,7=mod,alternate;name,Alternate
Scroll,8=mod,cross;name,Cross

Holds=6;
HoldsDefault=mod,no noholds,no planted,no twister,no nojumps,no nohands
Holds,1=mod,noholds;name,Off
Holds,2=name,On
Holds,3=mod,planted;name,Planted
Holds,4=mod,twister;name,Twister
Holds,5=mod,nojumps;name,NoJumps
Holds,6=mod,nohands;name,NoHands

Mines=3
MinesDefault=mod,no nomines,no mines
Mines,1=mod,nomines;name,Off
Mines,2=name,On
Mines,3=mod,mines;name,Add

Hide=3;
HideDefault=mod,no dark,no blind
Hide,1=name,Off
Hide,2=mod,dark;name,Dark
Hide,3=mod,blind;name,Blind
Persp=9
PerspDefault=mod,overhead
Persp,1=mod,incoming;name,Incoming
Persp,2=mod,overhead;name,Overhead
Persp,3=mod,200% overhead;name,Overhead
Persp,4=mod,space;name,Space
Persp,5=mod,hallway;name,Hallway
Persp,6=mod,260% Hallway;name,Hallway
Persp,7=mod,400% Hallway;name,Hallway
Persp,8=mod,414% Hallway;name,Hallway
Persp,9=mod,distant+;name,Distant