Everyone is expendable, so do not grow too attached to players and scores given the fickle nature of T20. If the order of scores was reversed for Clarke, would you still be as keen to hold through his bye?
I would be very cautious about selecting Hatz given you already own Agar. Do you expect the pitches to be spin friendly for RD2 and that the pace options for the Scorchers all struggle? Do you intend to hold any Scorchers bowlers past RD2 and would you be confident in fielding Hatz if necessary or that he is selected in RD3? In your situation is the cash saved essential in funding other or future moves? Seems like a low upside, high risk move.
Will be very interesting to see what coaches decide to do with their Thunder players and presents a great opportunity to exploit the Sunk Cost fallacy.
Out: J Clarke, R Rossouw and T Rogers
In: S Billings, A Tye (via A Agar) and A Lyth
Should be a solid option given your thoughts above