A lot of people have suggested a Rock/Heavy Metal themed table and I think that it has a lot of potential. Rather than stick to just one band though I reckon it would be more fun (and accesible) if they either get several songs from different bands or if that isnt practical for royalty reasons, come up with their own generic soundtrack. The music on the tables is pretty good and I'm sure they could come up with something suitable.
I'd like to see a drum kit at the top of the table on a transparent riser above the bumpers so that each bumper hit sounds a different drum, and maybe a rail that goes through the drum kit so that the ball hits the cymbols on the way passed.
You could have a ramp/orbit for each member of the band (singer, guitarist, bassist, drummer and maybe keyboard player depending on soundtrack) each making a suitable sound when hit. That way you could assemble the band to start with then take them on tour playing gigs. During gigs you could have it so each instrument starts playing at the start of the next bar after the ball has gone through - so that the song builds up and in a different way depending on which ramps you hit first (just to make it as interactive as possible without being too complex).
You could have gig style lighting too during this mode, maybe even fireworks on completion.
If you fail the gig mode you could have a simple 'penalty mode' (a bit like the breach in Secrets of the Deep) where you have to resolve the inevitable arguments, otherwise a band member has a tantrum and quits and you have to recruit a replacement (via the appropriate ramp) before continuing the tour. This should probably be fun rather than difficult (so that you enjoy the extra involvement rather than curse every time it happens).
The kickbacks should represent the unsung heros of rock - the road crew. The rails could be disguised as lighting rigs (with spot lights on them that flash as he ball goes passed).
Each gig could be a different song in a more prestigious venue, getting a bit more demanding and high-scoring as you progress.
In between gigs you'd have to rehearse (handled a bit like energy in Blade?) and get to the next gig (a bit like Pasha?).
The bonus multiplier would probably be down to PR stunts/media attention targets. You could even have it that successful gigs get you a better record contract that increases the base score of the ramps (though it might be nice to leave the money side of things out of it).
The multiball modes could be something like "Guitar Solo" (each lit ramp plays another face-melting lick) and "On the Road" (lock 3 balls in the battered old tour bus to start).
I reckon something like this would be loads of fun

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