To Quinn Morgendorffer as both of them are attractive and intelligent, but Daria downplays her looks and focuses on her intellectual pursuits, as opposed to Quinn who does the exact opposite.
To Jane Lane, who is an intellectual outcast but is much more willing to interact and show more emotion than Daria.
Quinn Morgendorffer is Daria's primary opposite in the series; a person who tends to pride herself on her appearance more than her intelligence (which she tries to hide), and visibly popular yet unable to form genuine relationships.
Mother Barksdale to "Mad Dog" Morgendorffer. The two of them employed rather questionable parenting towards their respective offspring, but whereas Mad Dog was horrifyingly abusive and domineering, Mother Barksdale overly favored one child and was neglectful towards the others. There's also the matter that Mother Barksdale is still alive and she's still showing this favoritism to Rita as well as Rita's daughter Erin.
Jane Lane shows herself to be more sociable than Daria Morgendorffer when she tries. Whereas Daria has been rather misanthropic since childhood (and not entirely happy with it), Jane's artistic sensibilities make her more of an outcast by choice. Their families are also contrasting, with Jane's relatively uninvolved parents versus Daria's driven and emotional ones.
Jodie Landon an intellectual equal of Daria Morgendorffer, Jodie is similarly cynical and frustrated, but still opts to be more active in the community, causing her no small amount of strife.
Jodie parents also serve as Foils for Jake and Helen, as they are both successful in their fields and have daughters, but while Jake and Helen allow Daria to be herself (even with her anti-social habits), Jodie's parents force her into school and social activities in an attempt to push Jodie to be her best.
The sharpest contrast has to be with Brittany Taylor. Both Jodie and Brittany are upper-middle-class teens with jock boyfriends and a high social presence, but Jodie is far smarter and despite having a more stable relationship with Mack isn't obnoxiously lovey-dovey; also while Brittany has a party thrown for her after getting a C minus by her father and stepmother, Jodie's parents hardly allow Jodie any opportunity to just relax.
Sandi Griffin seems to embody a version of Quinn who uses her intelligence for vindictive ends, rather than doing better in school. She also would not be above giving fashion advice that would eliminate the competition while Quinn genuinely gives fashion advice to people to help flatter their appearance more (case in point, Daria in "Road Worrier" and the obese Mrs. Johannson in "Psycho Therapy").
Mr. O'Neil and Mr. DeMartino are both nice exaggerations of 90s-00s teachers. O'Neil is constantly happy, uses positive messages/encouragement and tries to sugar-coat everything so they wouldn't be offended or discouraged. DeMartino on the other hand, is constantly angry and is much stricter on the students.
Mr. Anthony DeMartino is this to Daria Morgendorffer as well. While both are continually frustrated by the stupidity of other students, their approaches to dealing with it are complete opposites (Demartino's constant overreacting to Daria's snarking, which he even occasionally enjoys from her).
Tommy Sherman to Kevin Thompson, while Kevin is a Dumb Jock who's constantly Innocently Insensitive he's generally a Nice Guy, whereas Tommy is a strait up Jerk Jock who embodies all the associated negative stereotypes.
