I'm not really a Zepplin fanboy, but I can't help thinking that a Stairway to Heaven Wizard Mode with several successive drop targets *in* the ramp that have to be cleared to get up the ramp would be a fun thematic challenge.
Also, they could steal the no-flipper-hold idea and give a huge jackpot if the player can keep a ball alive for the entirity of Stairway.