It’s worth noting that the possibility of being tempted by the Light Side does not conflict with the canonical seductiveness of the Dark Side. The Dark Side is still a significantly greater source of temptation than the Light: it’s simply that, for the right person under the right circumstances, the Light Side can present a temptation too. As long as the temptation of the Dark Side is generally greater, people fallen to the Dark Side will tend to stay there.
Though there’s definitely a supernatural element to being tempted by the Dark Side, there’s also a more mundane element. The Dark Side plays upon one’s desires. Anakin, for example, fell because he believed the Dark Side would give him “the power to save Padmé.” For Kylo Ren, the Light Side would represent his family, the New Republic, and everything he lost by turning to Snoke. Unlike Anakin, it’s not clear that Kylo gained anything but power for its own sake when he turned to the Dark Side. It’s natural for him to have some regrets. Also, keep in mind the context of that scene. It’s referencing this earlier one:
SNOKE: There’s something more. The droid
we seek is aboard the Millennium
Falcon. In the hands of your father,
KYLO REN: He means nothing to me.
The “pull to the light” that Kylo is referencing is his feelings for his father, which are tempting him away from the path of evil that he has chosen. But this is nothing new—on the contrary, this is precisely what enabled Vader’s redemption: his selfless love for his son. Kylo simply has it a whole lot worse than Vader. Selflessness, and selfless love in particular, is certainly affiliated with the Light Side, so it makes a lot of sense for Kylo to describe himself as feeling “the pull of the light” here.
When considered in this broader context, then, other Sith Lords certainly have felt the pull of the Light. Even before his redemption, for example, Darth Vader experienced feelings unbefitting of a Sith Lord, and more charcteristic of the Light. In Lords of the Sith, for example, he prevents the Emperor from killing a young girl under the pretext that she could prove useful:
With preternatural speed the Emperor drew, ignited, and slashed at the
girl with his lightsaber, but Vader had sensed his Master’s intent and
moved with greater speed, igniting his own blade and intercepting his
Master’s blow before it could land.
Lords of the Sith
Later, he seems to admit that he was tempted by his past (i.e., lingering compassionate impulses):
Vader looked from his Master to the dark mouth of the mine inside of
which Drua and the rest of the villagers had fled. He felt the
Emperor’s eyes on him, the intensity of the gaze, the weight of his
expectations, and Vader knew that the day’s events had been only half
about depleting a rebel movement before it could grow. They had also,
as Vader had suspected, been about testing him, forcing him to face
the ghosts of his past and exorcise them forever and fully. He saw
that more clearly now; saw, too, that his Master was right to
administer the test.
Lords of the Sith
It’s not clear whether even Kylo Ren is being tempted by some supernatural power of the Light Side. But other Sith Lords (such as Darth Vader) have certainly been tempted by Light Side impulses.
Though the specific wording “pull to the light” is not used, Darth Gravid could be said to have been tempted by the Light Side:
A human Sith Lord whose short reign had elapsed some five centuries
earlier, Gravid had been persuaded to believe that total commitment to
the dark side would sentence the Sith Order to eventual defeat, and so
had sought to introduce Jedi selflessness and compassion into his
teachings and practice, forgetting that there can be no return to the
light for an adept who has entered the dark wood; that the dark side
will not surrender one to whom, by mutual agreement, it has staked a
claim. Driven increasingly mad by his attempts to straddle the two
realms, Gravid became convinced that the only way to safeguard the
future of the Sith was to hide or destroy the lore that had been
amassed through the generations—the texts, holocrons, and treatises—so
that the Sith could fashion a new beginning for themselves that would
Plagueis also described Gravid as “drawn to the light side,” which is similar to Kylo Ren’s statement about feeling “the pull of the light.”
The last Sith possessed of the knowledge had been inexplicably drawn
to the light side and killed, taking the secret process with him ….
It’s interesting to note that, like Kylo Ren in canon, Gravid experienced a great deal of conflict from his flirtations with the Light Side.