A small cloud of white smoke particularly after sitting is not uncommon. I've seen it with mine after sitting. I've also had mild bearing rattle at startup, and that is with 20k miles on the bearings. Not too sure what to say about the rough running. As it cleared up there's no real root cause. If it were me I'd continue to drive it for a few days to see if it repeats. If it doesn't give it a few weeks, if still nothing, a few months. Then it will be driving season again and your problem will be solved.
