Star Trek: 10 Things You Never Knew About Enterprise
7. T'Pau Was Originally Going To Be On The Ship Full-Time
Braga and Berman felt that the lower ratings of both Star Trek: Deep Space Nine and Star Trek: Voyager had been the result of those shows being less character-driven than The Original Series and The Next Generation, so Enterprise was intended to showcase its cast front and centre.
It was also decided that it needed to be linked to the franchise as closely as possible, so T'Pau was going to be the First Officer of the ship.
T'Pau had previously appeared in the Original Series' episode Amok Time, played by Celia Lovsky. It was she who presided over Spock's pon farr and supposed battle to the death with Kirk. She was, at that time, considered one of the most revered Vulcans of all time.
Having her appear as a younger version of herself would certainly have linked the series but there were those on the writing team who felt it might be too much. T'Pau became T'Pol, though she would later go on to appear in the fourth-season serial The Forge/Awakening/Kir'shara, this time played by Kara Zediker.