I missread the OP slightly. The gist of his question was could he use a relay.he is going to need more than 2 pole contactor, probable 3 or 4 pole contactor, based off the number of circuits he is trying to control.
This is what I wil say if I have a my own "It's a Wonderful Life" chance.There are 3 circuits involved, the 3-ways will switch the lighting circuit and the coil. The 2 pole contactor/relay will switch the two fan circuits.