Hopes: balance the warlord and wizard.
Fears: the warlord and wizard will not be balanced, or will be even less balanced.
Also, I think Johnny is misunderstood. It's not that he cares little for efficiency. Johnny loves to experiment and try new things. If a strategy looks fun but inefficient, Johnny tries to find a way to MAKE it efficient. Fun is more important than winning, but it's even better to be able to have fun AND win, and everyone knows that. I think it can be argued that all customizable strategy players who design their own builds have an inner Johnny.
When designing a spellbook I try to think of interesting fun ideas, and then after that see which ones I can make work.
Johnny's solution to inefficiency is creativity. Goblin Builder with Gate to Hell is a sign of an amateur or sleep-deprived Johnny, at least in the current meta as far as I can tell.