jaisa bhi ho they should take care of a few things.
make it entertaining, not boring like Don 2.
include some good songs, Don 2 album was really poor.
either Farhan should step down and get a new director, or he should realise the potential of this character and change his style.
make it a proper conclusion to the series, but do not include rest of the old characters.
once a brand has recognition, then the initial audience will show up. it is up to the makers to actually make a good movie. in that respect they failed miserably with Don 2 IMO.