This sounds more like a game setting than an RP setting.

We can't say for sure what it is about the description above, but something feels... missing...

Why would the Sith rescue the Jedi? Whats in it for him? What keeps the Jedi from killing him for being what he is?

Why would the others serve with each other?

We think you might have tried to bite too many pieces out of the Star Wars cake of lovely character types. We'd suggest focusing more on a smaller part of the potential types. Mandalorian bounty hunters are generally rare. True Mandalorians are warriors, not bounty-hunters.

For that matter... When are you planning on setting this up in the star wars timeline?

what sort of droid do you want there? an astromech? a humanoid one? Sounds a bit like you're trying to mix a protocol droid and an astromech into a single character.