Jacques has scored 9,460 first class runs at 56.98 (higher than Hussey's first-class average of 54 - not a patch on Hussey's test average tho I accept), as an opener and is only 27.
Hodge has scored 14,735 first class runs at 48.79 and is 32, 33 by the time next season starts.
Apart from maintaining the current team balance, I also feel the Aussie top-6 could do with a younger guy in the mix. With Clarke only 26, he and Jacques could start to form the next generation given that the other batsmen are all 31 and over. I'd rather give Jacques a go now than make him wait until Haydo goes, by which time Jacques could be 30.
Both would be worthy choices though and if the selectors do bite the bullet and shift Hussey, then Hodge is the man.