I think we're playing one dimensional football. I don't think we need to - even with the current squad.
What won't work is fielding players that can pass a ball and expect them to adapt to long balls down the channels.
As for the defence, Tait, ATS and Johnson can all play full back, and Aldred, Hartley, McHugh, Maguire (and Mbulu) can all play centre. So while it may not be his preferred approach, there's no reason we can't play a back 4 in the short term.