Here's my two cents:
I have brooded different species together without much of an issue. This spring I had gooslings, pheasants, and chicks together. Last year, I had a duckling, bobwhite quail, and both standard and bantam chicks together. I didn't run into any major issues that regular cleaning didn't solve. Once they are feathered out, I do seperate them as their permanent housing needs can be very different.
Quail can be a lot of fun, they are awesome to hatch and bobwhites have a pretty song. My quail live in flight cages made for finches until I can make them a child safe run of their own.