It all depends on if you want to pay annual fees or not.

For no annual fee, you can get Citibank Gold free for life (when on offer) or the Qantas Amex Card. $1=1 point/mile. Amex converts directly to miles. Citi involves gathering enough points and transferring them to miles in big blocks. The Qantas Amex offered 5000 points to join last time I looked.

For annual fees, you can get up to 2 points per $1, though 1.25 or 1.5 is more common. An attractive offer right now is the Qantas Amex Premium with up to 17500 bonus points. Annual fee though is $195.