yeah kensei's bankai is awesome too.. but i think is kinda weak.. i like shinji's bankai the reverse bankai.. it also controls your senses and make it reverse..i mean everything is reversed... that was the first time shinji shows his bankai..
Id like to see a Kido specific Bankai once, something like Tessai or Hacchi's Bankai. I wonder if its something that does a specific kido/bakudo that only they can do, or maybe enhances their powers...
And honestly I really do like Ichigo's Bankai but I would just use it better. Actually use its speed and focus on reiatsu control to make the blade as sharp as possible. Being super fast and super sharp would be instant kill I think
komamura's for the time being, even tho kubo essentially screwed the hell outta it by making that stupid puppet effect. most likely, my fave will become shunsui's, once shown.
MY BANKAI is pretty cool, if i do say so myself.
Senbonsakura Kageyoshi, because it has different forms, not just one... and it was the first awesome bankai ever shown in Bleach...almost like a terror (Renji pissed his pants lol)