One of the obvious problems with a relatively simple solution. Set a two term limit on all congressional and house positions to keep the focus on getting the job done, and not maintaining or jockeying for position at the trough.
These are elected positions by the constituency. Automatic or voted raises should be illegal. They are elected by the people and the people are their employers and as such should be the only ones authorized to alter their pay scale.
These elected officials should not be allowed to receive any gifts in office. If so, they should be dismissed instantly upon proof positive.