Will doing this adversely affect my results?
I'd say no. Baking Soda or Powder in the recipe would give up it's all sitting overnight and lose it's ability to rise the cake.
Definitely don't do that - no matter what your leavening agent (baking powder, baking soda, creamed butter, egg foam or some combination thereof) you need it to go into the oven quickly after mixing the batter.
You can mix dry ingredients together (less the sugar), pre-measure the rest, and that might save you 15 minutes the next day.
this is the best and only option for "Make ahead" batter.