One staple in BioWare RPGs is the chance to romance companions or even NPCs, something that has been honed and sometimes perfected across various games. Of course, one of those is Mass Effect, meaning that players will get the chance to re-kindle these flames over the whole trilogy come Mass Effect: Legendary Edition.
Now, this is not to say that any particular romance is bad in the upcoming Mass Effect: Legendary Edition, but they are not created equal. While they are all solid story arcs worth pursuing, some of them have a bigger emotional impact than others. For those who wish to experience the game once again as freshly as possible, be warned that this posts contains SPOILERS for the entire Mass Effect trilogy.
Kaidan/Ashley
In the very first game, all Shepards have two options: male Shepards can romance Ashley or Liara, while female Shepards can romance Kaidan Alenko or Liara. These two characters, generally speaking, are not the most popular because many prefer the alien romances and companions, but that doesn't mean they didn't come to to play. In the first game, the romance is innocuous enough until players have to choose between their friend and their LI, a difficult choice in Mass Effect 1; meanwhile, come Mass Effect 2, the relationship becomes strained due to Shepard's involvement with Cerberus and his prior death.
During the second game and well into the third, this becomes a point of conflict: Ashley/Kaidan will still love Shepard, but after having grieved and recovered, there's real emotional baggage when they realize Shepard is alive. For Ashley, this becomes a point of conflict with her faith, while any romance choices in Mass Effect 2, however temporary, play some role in salvaging the romance in Mass Effect 3. Overall, it's a rollercoaster of a relationship from start to finish, and it shows how well BioWare can make even the most "mundane" choices powerful.
Liara
Like Ashley and Kaidan, Liara is one of the "first love" options for Shepard, making this particular romance near and dear many hearts. Also like the other romance options, she has the added effect of mourning the loss of Shepard, and as it turns out, there's some added spice in that she gave his body to Cerberus. Liara doesn't give up on Shepard but tries to refrain from pushing him, an endearing quality that is seen in Mass Effect 3 as well. She mourns him depending on the ending players choose, but at the same time, it seems Mass Effect 4 shows Liara still hasn't give up on Shepard. It'll be interesting to see if she refuses to accept if he's gone, regardless of romance, as bringing back Shepard in Mass Effect 4 seems like a mistake.
Garrus
Of course, Garrus is one of the most iconic characters in the franchise, and romance with him can be really satisfying. With a nickname like "Archangel," it's hard to imagine his cool confidence giving away to vulnerability and fear, but that's exactly what a romance with Shepard does to Garrus. He admits being lonely, feeling like he has no one and worrying that a romance with Shepard will just put him back in that spot. Into Mass Effect 3, Shepard and Garrus become emotional supports for one another, as he worries about his family and the weight of the war bears down on Shepard.
When wounded near the end of ME3, Shepard sends him off and his face is one of the last things Shepard will see. His then continues to mourn her loss, as Liara does. However, what's interesting is that love is clearly in the cards for Garrus. If Shepard doesn't romance him or Tali in Mass Effect 2, they will enter a romance with each other, and it's a heart-warming moment for those who hate pursuing other romances. Garrus finds someone, seemingly no matter what, so he's not alone in the galaxy.
Jack
Jack's romance is easily one of the best, but it's heart-breaking to know that it was effectively neutered. It was recently revealed that Jack intended to be Pansexual in Mass Effect 2, but nonsense with Fox News saw that removed to avoid criticism. It'll be interesting if Mass Effect: Legendary Edition restores this option somehow, though fans shouldn't be expecting that. Nonetheless, Jack's hard exterior makes for an excellent romance. If players opt for the early casual romance for Jack, it won't progress further, but showing Jack actual attention goes a long way in cracking her shell. Once players see that side of her, it's clear that she's hard but loves harder.
Helping her work through her survivor's guilt shows a truly vulnerably side, one players may find hard to imagine after first meeting her, and shows how intimacy works with tons of nuance. It's not the hard attitude or physical romance that takes this option to the next level, but how modern and real romance in Mass Effect 2 feels with Jack. In the last moments of the romance, though, it's expression of physical need that really takes the cake, making it a somewhat light-hearted call for Shepard to come back. It's Jack's way of saying how much Shepard means to her.
Now, the only thing that could even remotely be changed about this romance without sacrificing its impact is, again, making her an option for FemSheps too. Since this is mostly a remaster of the trilogy, not a remake, it seems unlikely, but it's not impossible. Overall, Jack deserves her happiness and playing it the way it was originally intended shouldn't be something mods are needed to do.
Thane
With the Reapers, there is the constant threat of death in the galaxy, but with Thane, it's even more pressing. A deeply spiritual man, one who sees his body as a weapon and separates soul and body, he still somewhat sees his impending death due to disease as punishment for his wrong. These complexities make his romance pull on heartstrings all the more, as he is trying to forgive and love himself while finding his love for Shepard. If he survives Mass Effect 2's suicide mission, he is in the hospital and dying come Mass Effect 3.
He plays a major role in one plot and passes away in the hospital, with Shepard by his side. In the Mass Effect 3 Citadel DLC, this relationship is explored through his memorial and through the tapes recorded by him, ending in a "spiritual" scene between Shepard and Thane. Despite however it is interpreted, it's a powerful romance worthy of the BioWare moniker.
Mass Effect: Legendary Edition is in development for PC, PS4, and Xbox One, with targeted PS5 and Series X enhancements.