I wouldn't put too much hope in Tau Ceti. It's a G-type star like ours, but a type IV subgiant when ours is type V (main sequence). That makes it rather large and bright, for a start. If I remember correctly too, Tau Ceti is rather sparse in silicate, a material needed for planets. Despite the common anecdote, Tau Ceti is not a sun-like star.
