Will Gangplank get a full refund on his Q last hit?

With Kalista being able to rend a whole minion wave for free. with Cassiopeia being able to spam 0.2 second cooldown E's and actually GAIN mana as long as she keeps last hitting. Can we give GP a full refund whenever he last hits with his Q shot. This would be huge QoL buff for him and would really help him in the laning phase.