I do! It would probably be easier to set up factions for each group, like the soul reapers, vizards, arrancar, quincies, bounts and fullbringers. As for following the main plot of the story, I believe it should be changed slightly, but still follow some form of plot from the series.
It would make it more interesting to include all of the races from the start unlike in the plot, but that would make the entire thing kind of boring, so it would be great to have the OCs incorporated, but not having certain characters reveal their powers, abilities or race until that time comes. Personally, I think it would be best to maybe have it to where people choose if they want to be in Ichigo's group, start in Soul Society or Hueco Mundo, there are a lot of possibilities to be had here. Each character's story would be different unless they were with a certain group.
It makes it more interesting to have different people on different paths. Then, there is the possibility of doing a backwards time skip, in where the vizards (Shinji, Love and the others) are still soul reapers, similar to the anime, but we include Ichigo's father, our own OCs, maybe Ashido (from Menos Forest), and even a lot more quincies and have a lot of conflict. There are a lot of possibilities for a Bleach RP, so it's hard to choose. Heck, we could do the time skip into the future and start there, or even just make a spin off completely alternate universe type of plot, similar to what they're doing with the new Naruto movie (Sasuke give flowers to Sakura!! Please, someone agree with me this is just messed up!!)
We could do a group and make separate threads for each group and for people who want to do a certain plot line or time line.