Selling an 8.1 to 8.3 upgrade

I've been asked to put together a list of reasons to upgrade a db
from 8.1 to 8.3 and I've looked over the changelog, but they want a
bullet list of 4-5 top things.  I'm curious what others would say the
most 5 important updates from 8.1 to 8.3 are.

I can say "performance improvevents" but I'm not sure how to sell
that better other than listing what's in the release notes.  I also
think the autovac was greatly improved in these releases as well?  Or
maybe I'm thinking 8.0 to 8.1?

Sorry this is so vague, I'm frustrated with this request as I figured
just the amount of bug-fixes alone would be adequate reasoning.

Thanks,

Josh