Hmm let's see here:
Violet has Tony (official pairing although we'll see how long that lasts when the sequel comes out), but she gets shipped with Wilbur (MtR), Syndrome, Hiro (BH6, although that pairing has just formed), Jack Frost (RoTG), Hiccup (HTTYD), Mirage (yes there are some fanart with these 2 as a couple), and Raven (Teen Titans, and yes there is fanart of these 2 as well).
Helen/Elastigirl is already married (Bob), but she only has 1 person that people really ship her with and that's Dr. Draken (Kim Possible), plus people are too busy blowing her up like a blimp these days rather than pairing her up with fanon pairings.
Jessie has Buzz, but there are people who believe that she and Woody are perfect for each other (they're both cowboy based toys).
Rapunzel, Anna, and Merida tend to get the same pairings as one another, (Hiccup, Jack Frost, or Hiro Hamada).
Jasmine's pairing tends to be Aladdin (and like Elastigirl, she gets more of the blimping moreso than fanon pairings).
Black Widow, Gamora, the 3 female emotions, Mulan (not sure, but she's already married as shown in Mulan II), Quorra, and Tinkerbell really don't have anyone that they get paired up with often, so can't really tell.
Minnie has Mickey (techinally 2 Mickeys if you throw in his Sorcerer's counterpart from 1.0 into the mix, but then what Minnie has 2 Mickeys to fight over).
Vanellope tends to either get paired with Dash (thanks to Disney Infinity), Ralph or Hiro Hamada (again thanks to Disney Infinity, even though I prefer Hiro being with Violet).
Leia has Han Solo to worry about (and possibly mourn over, if the Han death rumors in Episode VII are true), Ashoka tends to get paired with either her master Anakin, or Barris (that jedi girl she got paired up with during the Clone Wars and got into a rivarly with) then again it's illegal for a Jedi to fall in love anyways (that's what caused Anakin's turn to the darkside in the 1st place), plus these 2 just got announced (along with Joy and the 2 other emotion girls and Mulan).
And yes you could pair all the females up with Spider-man if you want (including Star, should she get in) hench the Infinite Possibilities, he's the perfect age for most of them at least (his Ultimate cartoon counterpart is around 14-15 years old) heck if you want to take it up another notch pair em up with whoever you like in the game, Maleficent and Elsa's pairings are overused to the point where it just bores me and Holly never gets any love because she came from 1 of the worst Pixar films ever made (Cars 2, not only that she had a crush on Mater throughout the movie, or was it the other way around?)
Most of the shipping tends to be on Deviantart anyways, but be warned if you're brave enough to stomach looking up your favorite characters without seeing them ruined by god knows how many fetish fanart they made out of those said characters.