Honestly just renaming them using the Tombstone of L and D, Sim Blender or editing in SimPE is your best go to.
The simplest is to enter 'boolprop testingcheatsenabled true' in the cheat box BEFORE you play a household or if you already there type in the cheat, save then go back in. Then press 'shift' and click on your sim and you will see a bunch of options choose 'Spawn' then you'll see 'Tombstone of L and D' click on it. Once a tombstone appears on the ground click on it to 'rename your sim'. You can enter Dr. and Mrs. or whatever you'd like.
If you have the Sim Blender going to 'Names' then 'rename a sim' is also very easy.
I hope this helps and is what you were looking for.