Yes, I suppose what spells you able to end up getting is random.
In my new game I managed to get both sac+res eventually and never have to recruit troops.
Sorry for the large 1900x1200 ss, and it's funny, on some fights if I stack all the int I can, I Geyser twice at the start and thats enough dmg to kill alll the troops in 1 turn. This isn't normal mode either, I'm playing as hard but it's feeling very easy, Impossible level will be within my grasp next game I think.
My frog wife gave me kids that that +40%mana, +20%int, +20%def combined so I've been roaming around with a ridiculous amount of mana (150-200) and very high int (29-36) depending on what I'm gear using.
Hyponizing then sacrficing enemy troops is extreamly effective, I have almost 2 million gold becuase I never have to pay for troops.