I've always thought that Sakura's affinity would be water, as well. People always say that they think she would be an earth type (and that if she was a bender she'd be an earth bender lol) and depict her as such, but I disagree. It's because of her strength that they think that way (and she is 'down to earth' so that could be another thing relating to her as an earth user), but there's much more pointing to her having an affinity for water imo. Water is known as the healing element, and Sakura's a medical ninja, primarily so. She also has a certain duality about her that is similar to water's: she's calm, rational, and is peace-seeking, like peaceful waters, but she can get angry, like raging waters. And, though it wasn't classified as a water type jutsu, the Delicate Illness Extraction technique looks like it would be waterbending haha.Well, I still think that if Sakura is going to have to do with any natural element, that'd be water, the only one missing in team 7, which funny enough we've seen that katsuyu liquifies herself... so maaaybe, if Sakura gets SSM like I presume, she'd also get a SSM and a natural element, two from one shot kinda thing and would also be no need for ass pulls if properly explained. Plus, there are those Kaguya similarities and stuff... Meh, who knows?
Although, there's no one with an earth affinity in Team 7 either, is there? Kakashi has used earth techniques, yeah, but he's also used water techniques, while his affinity is lightning..