Analyzing Rita, you're naturally going to draw comparisons to the two other Evasion-focused survivors, those being Wendy Adams and Stella Clark. All three have mediocre-to-poor investigate and fight stats, but while Wendy and Stella have powerful abilities to offset their weakness, Rita's ability goes all-in on her strength, evasion. This is...a little strange.
5 agility is the best in the game at the time of writing, and her ability grants a free move action or free damage out of an evasion test once per round. That's great. If you have to evade, you almost always want to move away or inflict damage as well. If her ability was an asset, it would be an auto-include for any high-agility character. Where she falls frustratingly short is how she applies that agility when there's no one around to evade.
Her biggest handicap is that survivors have precious few cards to capitalize on 5 agility. Those are almost exclusively in the rogue pool, which Wendy Adams has vastly broader access to. Rita has better agility, but cannot Backstab. She cannot use Lockpicks to mitigate her poor investigation. She cannot use Pickpocketing for draw economy. She cannot use Suggestion to easily evade anything in the game. She instead has a pool of (currently) 16 cards outside of the survivor role, all of which are rogue, and only two are not also available to Wendy.
So what does she have instead? In terms of card access, Ace in the Hole and the upgraded Pilfer. Ace in the hole is very good (and combos amazingly with Will to Survive), but a single card that you may never draw isn't exactly compelling. Pilfer is useful, but incredibly expensive. Without rogue money economy, she'll be hard pressed to actually use it after bouncing it back to her hand.
In terms of card utility, she has one major advantage over Wendy, and that's her fight value of 3. The survivor pool is a little thin compared to guardian or rogue, but she can make decent use out of a few clutch options. She can even spring for something more substantial if necessary. Evasion is helpful in a pinch, but the ability to remove a threat completely can't be understated, and Rita has a consistency there that Wendy can't match.
As for the Stella comparison, that's a bit more nuanced. Their statlines are nearly identical, with Rita getting a bonus point in agility, but Stella having a whopping 8/8 health/sanity pool. While Rita will stay glued to Peter Sylvestre for dear life, Stella can take whatever is thrown at her. Rita has the (slightly) better card pool, with access to Sleight of Hand if she's using her guns, or to get more keys out of Old Keyring. She can Swift Reload her hunting rifle, and like Wendy can fleece Easy Marks for an economy boost.
Stella on the other hand has the much-lauded combo of Drawing Thin and Track Shoes. While Rita can also use it, her higher agility (much higher if running Pete) means you'll actually have a hard time intentionally failing the test on track shoes, and usually run right past your target. Stella tests flat, and gains a bonus action from failing. Point to Stella; that's some of the best economy in the game. Stella's ability also wrings more efficiency out of the suite of failure-specific survivor cards like "Look what I found!" or Dumb Luck. Stella's signature cards are universally useful, while Rita's is situational at best. At the time of writing, I think they come out about even; Rita has the edge as a multiplayer evader, while Stella excels as an all-rounder.
In summary, if you want to lean 100% into sneaking and tricks, you'll like Wendy. If you want to get your hands dirty sometimes, you'll prefer Rita. It you want to draw autofails all day while singing "ain't nothin' gonna break my stride", go with Stella.