Depends on the seed tables. If you are enhancing at the events you’ll have a more inline enhancement of fails and successes. As more people are enhancing ; levelling everything out.
You could enhance after, however, it’ll either be good since the seed table is ready to give out enhancements or bad since it is not.
End of the day it is all down to luck. It is way better than it use to be !
Iirc t3 enhancement was never adjusted so that tier is still on the old rates which do suck.