A 34 ACT is fine. If your daughter wants to retake to hit a 36 for full rides at your flagships, that’s fine, definitely do that. With an initial score of 34, taking the ACT twice won’t look bad at all to Stanford. Generally, universities (although they say they don’t) are somewhat cautious of an applicant who took the SAT 6 times, going from an 1800 to a 2350 or something. In your daughter’s case, they know she’s qualified, and taking it twice won’t affect her application at all (and I’d suggest doing so if she thinks she can get a 36, although 36s are rarer than 2400s on the SAT).