While I still feel like we should have gotten way more of Elita in TFOne, I do like what we saw of her and how she serves as a contrast to D-16. This especially goes for their respective relationships with Orion.
D-16 and Elita are pretty similar when you think about it. They are both pretty serious and driven people who both earnestly committed themselves to the system in hopes of climbing the latter.
Though its worth noting that while Elita is very proactive when it comes to climbing the latter, constantly chasing promotions, D-16 is much more passive, choosing to keep his head low and slowly but steadily work his way up.
When they learn the truth about Sentinel Prime's rule and how they were deceived and exploited, Elita does not lose herself to anger the way D-16 does, despite her intense devotion to succeeding within the system being her defining trait up until this point. I wish her feelings on the matter were explored more, but its clear her focus purely becomes about exposing Sentinel and freeing her fellow miners.
This is where Elita and D-16 go in complete opposite directions in terms of character development, which is illustrated in how they treat Orion.
D-16 completely shuts Orion out, even becoming aggressive towards him and blaming him for the pain of learning the truth. He completely disregards anything Orion has to say, paying no mind to any plan or strategy Orion proposes. He starts to treat him as a hindrance, and even before their relationship began to degrade, he was very reluctant to take part in Orion's "schemes." This of course, is what culminates in "I'm not saving you anymore" and D-16 deciding to drop Orion.
Then there is Elita, who in Orion's darkest hour, takes it upon herself to try and uplift him despite her inexperience with any sort of emotional intimacy. She makes it clear that she values his plans, his optimism, and his rebellious nature, everything D-16 grew to resent him for.
Both Elita and D-16 have very aggressive personalities, but while D-16 uses his to dominate his way to the top of the decepticon hierarchy, Elita uses her's to uplift Orion. She commands the attention of the other miners when Orion is too soft spoken to do so himself, and together they lead their people against their shared tyrant (much like what Orion wanted to do with D-16).
I personally love this dynamic between them. Elita having already mastered the assertive aspect of leadership, without the ability to adequately inspire or be charismatic; whereas Orion/Optimus brings the ideology and charisma to the equation, without the ability to properly assert himself in a way that leadership requires. (If I'm allowed to be unserious for a second, its very "Excuse me! He asked for no pickles")
While it's unclear if the writers intend to pursue a romantic arc between Optimus and Elita in the sequel, it's obvious by Optimus' decision to make Elita his Major that they will be working very closely with together going forward. While Orion may have been powerless to preserve his relationship with D-16, Optimus' relationship with Elita is the one he will be forging going into the future.
