So like, first of all it would be great if you could walk around in the taunt like the Conga, no killing tough too OP. You could also perch like the Rancho

Have spy make little funny comments while using it, and have an option for if the player doesn't end the taunt, another player can walk over and interact with them and remove the box thus exposing Spy and getting a reaction.

Also, since most of us know what this is clearly referencing, when you are killed while in the taunt, people in the nearby area and yourself hear the announcer:

"Spy? SPY? SPYYYYYYYYYYYYYYYYYY!?!?"

Make it happen.