score:6
It looks like at least one shuttle service stops their regular service at 8pm, but continues a night shuttle service until 5am.
However, TaxiAeropuerto (the bright orange taxis) offer 24/7 taxi service from the airport. I apologise if you can't read Spanish, mine isn't so great, but a rough translation of the last two sentences on that page is all you need:
Likewise, we transfer to the airport. We offer 24 hours service, 7 days a week
I imagine calling them to reserve might be a way to guarantee a pickup, but otherwise yeah, it sounds like you'll have no problem there.