As of yet there is not a functionality that allows for you to define study parameters in a part and then insert that part and all the Simulation boundaries into an assembly. Presently, a way you could accomplish this would be to start inside of the assembly you wish to analyze, create setups isolating the particular parts you wish to analyze while excluding all others, then re-include other parts of your assembly as you wish to then include them in your analysis. In that way you are not duplicating efforts on fixtures, contacts, loads, and mesh controls. You just have to start and stay at the assembly level in order to do that.
Would you demonstrate the solution via some example?