Her only problem is that her learned abilities are limited and she has morals. Sakura doesn't even have to train in learning attacks, the only thing Orochimaru would help her tone is her tai jutsu like Tsunade, and he would break her moral code and she will learn darker jutsu
You are wrong. Orochimaru could teach her even more than what he could teach Sasuke.
Sakura was said to have the best chakra control out of T7 and had a talent for Genjutsu. Moreover, she was the best in terms of learning.
Under Oro's guidance, she would've learned/gained:
-Snake techniques - just like Anko
-Cursed Seal (since we consider it a swap, so for the sake of the plot she would have to survive the injection)
-More diverse Medical Ninjutsu - Tsunade couldn't have given her what Oro would've. She would have an access to tons of human bodies, she could experiment on them and carry out research. While under Tsunade's guidance she could heal some fish or small wounds...
-She could expand her Genjutsu skills, considering that Orochimaru had 5 in that area.
-Fuinjutsu - Oro was an expert on that field and since Sakura managed to create a Yin Seal, she probably could learn barrier and sealing jutsu.
-All the Kinjutsu Orochimaru has taught Anko.
-Probably could explore her elemental affinity.
-Would learn Kenjutsu just like Sasuke did., since Orochimaru was an expert in using a sword.
The only downside would be lack of CES.
@edit
I forgot about the poison immunity, ruthless character and the massive knowledge Orochimaru has.