Well if your at normal level your slow, weak and your HP is is lower. If you go SSJ you become faster, stronger and your HP rises and sometimes you gain new attacks. If you didn't notice with SSJ Goku you can power up a kamehame ha and teleport doesn't that just blow your mind?!
Also if you notice when your pl is getting higher from first turning SSJ it takes a while to transform I think if you break a point it keeps taking less time then when your usually around 6 million pl without turbo you can transform at will which means you push the button you transform no waiting instant transformation. I hope this helps and if you have any other questions drop by IRC on GamesNET #esf