If you want good cast bullet performance on deer size game you want to cast towards the soft side & don't even consider water quenching, it's seldom needed anyway. Now that powder coating has passed the smell test & almost everyone has accepted it you will find that you can cast your bullets a bit on the soft side, even without a gas check by powder coating & get outstanding results.
I'm talking about using HP's here. If you want more penetration on bigger game like elk, bear, etc then you can use solids & bump up the BHN just a bit, again with powder coating & be very happy with results.
A well known gun writer friend recently run some of my gas checked HP 41 bullets over 1700 fps from a rifle with groups under 3/4" with 4 different powders. These bullets were soft but powder coated.