Before you book out of FRA, have a look at prices from MXP, IST and ATH (also check the difference if you return to London/Manchester/EDI etc). And EY also has periodic sales ex-BRU. Also check fares to BNE which are sometimes less than SYD.

The rewards program was massacred recently, so you won't earn enough miles to do anything significant unless EY has one of their 50% off awards sales. Possibly you can get better value crediting to a partner like AA.

On the plus side their awards are usually wide open and plenty of upgrade space if you have enough points.