I'd say Rock Lee is a lot more of a competent ninja than Sakura. Minus the healing powers obviously. But more importantly she's just an awful character, I mean we can argue power levels until we are blue in the face but you already pointed out, naruto and sasuke are on different levels entirely. She just has absolutely garbage development, she's not like-able, she doesn't follow any creed, she has no depth and only ever whines that sasuke isn't paying attention to her. Ability wise she is just an offbrand Tsunade, nothing unique about her. Yes Naruto and Sasuke were born special but at least they added on to their mentor's teachings. So did most of the Konoha 12, or Gaara, Temari, and Kankuro- they all added something unique, went further then their mentors. I'm not even sure Sakura is as strong as Tsunade, but even if she is she's just a bad copy with a worse character.