Your idea involves "wasting time" of leveling all the way to a final form. The actual cost of the edge doesn't change the end result in that someone deletes if they get a form they don't want to play.

Reducing the cost of the edge will just further promote the idea of a throwaway shifter because you will literally need to do nothing beyond power level. At least if we went down the road of exemption yourself from a single form you could go in treating the character as a serious one from the gate.