Centrair Airport to Ise

I would like to travel down the Ise Peninsula from Nagoya Airport. I see there are ferries to Tsu from Centrair. Would this be a good option to catch a train or bus to Ise from? I will need lodging the night of 8/10 - any recommendations for 3 people? We will be continuing on to Nachi waterfall to stay on 8/11.

I would like to travel down the Ise Peninsula from Nagoya Airport.

Ise is located on the Shima Peninsula. And Nachi is located on the Kii Peninsula.

I see there are ferries to Tsu from Centrair. Would this be a good option to catch a train or bus to Ise from?

Yes! There is also a ferry to Toba, which you could also consider.

About the Shima Peninsula:
http://www.japan-guide.com/e/e4310.html

Be warned that if you have not yet made hotel reservation for the area around Nachi, it may be difficult to find accommodation for around August 11 now. It is the peak of the summer holidays.

Okay, so I can take the ferry from Centrair to Tsu and then get a train to Ise, but I'm on the wrong peninsula for Nachi waterfall?
I have reservations on 11th for the temple at Nachi waterfall.
How far from Ise is it?

Okay, so I can take the ferry from Centrair to Tsu and then get a train to Ise, but I'm on the wrong peninsula for Nachi waterfall?

The Shima Peninsula is along the way from Nagoya down the Kii Peninsula. See the map below (Toba is close to Ise on the Shima Peninsula, while Katsuura is near Nachi waterfall at the southern tip of the Kii Peninsula):
http://www.hotel-nakanoshima.jp/english/access/map01.html

How far from Ise is it?

The train trip from Ise to Katsuura takes about 3 hours by express train with one transfer at Taki Station near Ise.