I'm assuming Air Baltic and Etihad have an interline agreement as they codeshare on many flights. Make sure they'll check through all of your bags to SYD. You'll arrive in Terminal A or B (Schengen area) and will take a short train to Terminal E (non-Schengen area) for departure on Etihad. You will have to go through passport control but this shouldn't take long as its before peak time. You don't have to go through customs as you're leaving on an international flight. Go to the Etihad transfer desk or straight to the gate to check-in for AUH and SYD. It's doable in 15min if you're in a hurry. MCT at ZRH is 40min, that should be enough time for both passenger and bag to connect from any gate to another at the whole airport. This is true even if you're holding seperate tickets, although in this case the airline won't be responsible if you miss the flight.

In case they won't check your bags through, go collect your bags at the belt and proceed to the exit and then Check-In 2 Row 1. You'll need a little more time but 30min should be enough to deboard, collect your bags and arrive at the check-in. Once you're at the check-in and it's still open, you know you'll be fine. Barring any special irregularities, your flight will be on-time anyway.