CRJ-200's are probably the worst when it comes to W&B issues. They are almost always nose heavy, so the answer is to move people to the back. Cargo helps too, but when people don't have enough checked or valet bags there has to either be weight added to the cargo or sometimes it's easier and quicker to ask for someone from the front to go to the back. Fuel loading plays a factor as well. The higher the fuel load the CG will move aft as well. But on short flights they won't carry as much fuel.