Just in terms of Mass Effect, I've had characters who preferred Liara, and ones that preferred Kaidan (almost no one would prefer Ashley, because she almost always dies on Virmire - and the one character I played who probably WOULD have preferred her couldn't date her because she's not bi/lesbian). My Ruthless Colonist Shepard who was a xenophobic racist wound up with Garrus (which I didn't actually plan on happening - it just sort of evolved organically, mostly because the Jacob romance is brutally strict and I failed out of it without meaning to - which made it a really interesting narrative when it happened because it felt like it was super out-of-character for her, but also simultaneously had happened entirely organically and unforced... she'd essentially evolved as a character). I've had characters who break up with Kaidan over Horizon, and ones that stay loyal and rekindle things in ME3.
Man. I really hate it when people say they killed off Ashley 'because she's a racist/xenophobe' because...
First off, if you actually pay attention, she's not xenophobic from the outset. She doesn't trust aliens because she feels that they don't treat humanity as equals yet. We do see this play out multiple times across all three games in which various aliens treat humans as lesser/inferior due to being a new part of the galactic community. Secondly her fears about what the council would do to humanity were SPOT ON! They threw humanity under the Reapers to try and buy time to protect their own worlds. They even did sort of the same with the geth whom they let humans and human colonists fight off/get killed by instead of responding with proper force or even sending a specter to investigate. That's not to mention that having a bunch of aliens, not all of which have even demonstrated loyalty to Shepard beyond their mutual desire to take down Saren, on the most cutting edge ship humanity had at the time was a very risky move. She has no problem working with the aliens personally and even outright says she'll follow her orders no matter what. Shepard says 'kiss a turan' and she says 'which cheek'. She outright refuses and rejects the pro-human racist group in 1 as she recognizes that they care more about hating aliens than humanity, in 2 she refuses to join Shepard because she detests Cerberus that much because of how they treat aliens, and in 3 she's not only become a specter, which is a tool of the council, but she's forged close bonds with the likes of Tali whom she outright compares to a little sister. Yes, she puts humanity first, but she's not racist. She treats aliens with respect and as friends and rejects racism. She isn't perfect and her dealing with her issues is part of her character arc, but it's clear if you pay attention that she's also not about to treat a race like they're inferior or anything. Not saying you kill her off on Virmire because of that, but that's by far the most common reason I hear for it. Drives me batty especially knowing she was right.
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I am the gentle hand who heals, the happy smile who shields, and the foot that will kick your ***! - White Mage