For pvp 190-200% to be comfortable in most cases. You never know if someone puts dodge stones on other partners except vanguard etc
If the enemy has some partner which specializes in dodge like Ruuken or Stark with exclusive then you will need more.
For pve like ryoka or ES I honestly have no idea what is the minimum but you wont need more than for PVP.
In case of Void or Aizen fight in hollow soul 300%+ to be comfortable.
Yep he already did that. Honestly these days it is just super easy with all these OP event partners, zanpakutos, red tavern partners, ultimate eq and the crap load of other things which boost your power even further. Back in the day it was a real challenge. Still remember how I did 1v1 with shura ken and then followed with full control team of tavern partners and stun skill for main in 5v5 to have a chance