Allowing players to carry over leadership between turns is slowing match progression. With the current system, players have a large amount of control over how much VP their opponents have access to. While this can creates some interesting strategies, in most games it results in players not throwing down units until they need to respond to something (and also tacking an extra couole of turns on to the match).
Also, turn 3 zapper is a beast and it may be very difficult in the future to continue to add big expensive game ending units.
Suggestion: change leadership to allow players to carry over one unspent leadership per turn. This will still allow players to play off curve so they can throw something bigger down later if they want to, while incentiving players to play units early so both players can score more points.

Honestly Zapper itself seems to be more an issue as it allows for almost No counterplay beyond, Have a Stun Unit allready or Use the Furia Build.