Are crowns/veneers supposed to have any ridges or be perfectly smooth?

Teeth are not flat.  They are smooth and shiny, but have undulations as you describe. The better the lab is, the more texture you get.  Flat teeth look fake, so it seems you found a good dentist with a good lab.

If you have texture in your crowns or veneers it will see more real and natural. many doctor put some flat teeth and in long term it just cause problems with your gum. Everything in nature has a reason to be.
Regards,
Dr. Alfonsina Hdez R