Creating new parts

Looking for tips on creating new parts in assemblies.

My current method is selecting the front plane of the assembly andthen exiting the sketch so that all of my planes match up [that wayit is easy to delete the "in place" mate and replace it with"relation mates"]. My problem with this is that the firstsketch/feature of the new part ends up being offset from its ownorgin. Also, if the first sketch plane is on an angled face in theassembly then it too is angled away from its own orgin. This makesproducing drawings difficult.

Is it better to locate the new part on another part instead of atthe assembly orgin?SolidworksAssemblies