Which spells do you base your spells on?

Which are the best base spells to create trigger enhanced spells?
which one's effects can easily be removed

which one is the best for spells targeting points/targeting units/with no target?

It depends on the end effect you want. Also something to keep in mind is, you cant have two spells with the same base skill for one unit.

As for the spell with no effect...you can do this with almost any spell, but the animation of the unit will remain the same.

Break.