Soval was one of the more prominent Vulcans in the series. He was the Vulcan ambassador to Earth, but before then he was involved in the conflict with the Andorians, serving as an intelligence officer.
While Soval wasn’t a very beloved character, he was shockingly very complex. Far more of an antagonist for the Enterprise crew, Soval was never truly a villain, just a pain to deal with. That made him fall further down the list than others did, mostly due to his general annoyances. His usual involvement with the series was unextraordinary except for two things. First, he looked like Mr. Smith from the Matrix but if Mr. Smith was a Vulcan, and secondly, his involvement with the Andorians.
The conflict he brought with him in any Andorian-centered episode was entertaining as heck. Soval’s actor, Gary Graham, seemed to be at his best when he was paired up with veteran Star Trek actor, Jeffrey Combs.
While they didn’t share much screentime, the episode that features their more epic encounter, season two’s “Ceasefire”, remains among the series best, in part due to Graham and Combs.
Soval was the focal point of revealing many mysteries behind Vulcans, like their paranoia and historical disrespect of other species. It showed that Vulcans, at least in the time of Enterprise, weren’t the fully evolved creatures we’d come to find out. They had their secrets and Soval was the introduction to that.