I think that would largely just remove the appeal and use of profession-swapping in that case, lowering the fun in choice that comes with optimizing what to do when you're in that scenario
I do agree that the side of the profession could get a buff, but I think a more unique change than mimicking sell modifier would be nice. It's inherently limited by the cost and slow starting up of animals as a whole so it doesn't have to be equivalent and perfection equal, but it could be nice to have a little more balance.