Madara - High jounin, low Kage
Itachi - Low Kage
Shisui - Hard to tell but based on his speed hype I'll say high jounin
Izuna - same as Madara
Sasuke - low jounin at best
Obito - hard to say. I'll say med jounin
Depends. They would be like everyone else. Kakashi is a good idea of how their power levels would drop without sharingan.
Then again the sharingan is their main skill, so it's like taking away Hashirama's wood style.