You do realise that McGregor is contracted for next year too, don't you? So honouring his contract would mean throwing away the 2017 season and upping our bullshit rebuilding years to 6 in total, plus however long it takes a competent coach to actually rebuild the team.
Sacking him now will show that we are not happy with the mediocrity that runs through our club. It's a start at least. Announcing a new coach sooner, rather than later, would allow said new coach to start looking into recruitment and building the squad they want for for next. Hell, if we announced a decent coach like Madge or Cleary it might even sway some players that are considering signing but currently unlikely. Allowing someone like Demetriou to act head coach in the mean time will give our players a shake up, allow some new combinations and there's a chance he could work with said new coach to bring certain players through and see if they are worth holding on to.
SOOOOO MANY BENEFITS. As I said, we've got no integrity anyway, better to start the long term gain now.