I put my ARB bumper on last summer and wheeled with it all summer long. I think I lost about 3/4" of ground clearance. If you are wheeling some harder trails you will be looking to gain back the clearance... The good news is even if you didn't add the bumper and you where wheeling the harder trails you would be looking to gain some height.
Just one word of warning once you start doing mod's its hard to stop
I also don't thing there is a proper order to start your mods but if this helps heres the order I started in
I think I'm at a point where I am going to leave it for now... I could put 35's on it but think I will wait untill I identify the 33's as a weekness.