yes
use a teaspoon of lemon juice. The whole purpose of "rind" is to give extra flavor. Decrease the liquid by one teaspoon of the other wet ingredients.
Try any citrus fruit, such as Lime or Orange.
Lemon zest is the very thin yellow layer on the rind of a lemon. It contains lemon oils which are very pungent. The white part of the rind under the zest is bitter and shouldn't be used for baking or...
Yes, lemon rind and orange rind are not that molecularity different so you shouldn't encounter any change in taste.