Last wish maybe has its own use in Spell ST deck as a deck thinning card. But still that card is too weak if it only draw 2 card. Maybe it will start see play if it draw 3 cards instead. But you will be better off replacing it with any other neutral drawing card like Sarah.
Throwing the round would be a bad usage of such a spy, although sometimes you have no other options. The CA spy is important when your deck requires you to have CA. But it can also be important when you are running weather/control and need a unit on the opposite side that can be damaged. The CA spies can be very important as long as your deck supports such tactics.