The TOS bridge stations seemed more programmable.
The jelly bean control buttons were quite similar for all stations and generally non-descript. You could believe their functions were programmable and variable.
TMP onwards, the bridge stations featured controls that were more specific and unique. I'm thinking of the PhoTorp loading controls and the Comm frequency slider as examples. Specific controls, individually labeled. Seems awkward to re-purpose the clearly labeled Phaser Charging buttons, whilst the TOS helm featured more general purpose buttons that could do, well, anything the script needed.