Seeing as how @RedStreak3795 did a whole thread on why he loves Rosie so much, I figured I’d throw in my two cents.
Here’s a thread on why I love the character of Lexi from "Journey Beyond Sodor”. (1/?)

First of all, she’s unique.
Look at her: she’s a cab-forward engine with a rusted sky blue paint job and runs on these two barrel things on her little fuel car.
We’ve never seen a character like Lexi before or since in the show’s history, and I love how she stands out.
(2/?)

Secondly, the fact she can do such a wide variety of voices and accents (from Scottish to French to Bronx to even Batman) is remarkable; it gives off the sense she doesn’t fully know who she is, so she crafts her identity from various voices she’s heard throughout her life.
(3/?)

Her relationship with Theo and Merlin is honestly adorable; the way they look after each other despite the fact they 'can’t do anything’ gives off a brilliant sense of camaraderie than some of the other trios in the franchise (including the Logging Locos).
(4/?)

Their song slaps. You can’t deny it.
(5/?)

The fact that we never saw more of her after JBS just annoys me since I always believe in the potential of a character; based off her chatterbox personality, I was really hoping to see an episode with her interacting with Marion (who I lowkey ship Lexi with).
(6/?)

I love Lexi so much that she appears frequently in my human AU since the very beginning; most of the time with Marion due to my aforementioned shipping of them.
(7/?)

The mere fact that a character like Lexi - a strange, experimental cab-forward locomotive - exists amongst a giant ensemble cast is astounding; seeing her amongst all these front-facing characters just makes her all the more able to stand out.
(8/?)

She’s also the only Thomas character that I have in all the merch lines she appeared in; Trackmaster and Adventures.
It sucks that they didn’t do a Wooden Railway version of her, which I always imagined looking similar to @StreakSmeargle’s awesome concept design.
(9/?)

In conclusion, the reason Lexi is my favorite Thomas character that isn’t Ashima, Millie, Emily OR Caitlin is because of just how unique she is.
There’s never been a character like her before or since, and I honestly wouldn’t have it any other way.
(10/?)

There may be a wide variety of characters in the Thomas cast, but I will always remember the experimental cab-forward engine from the Mainland; because there will never ever be another engine like her.
Thanks for reading.
(11/11)