Quoted from Mbecker:

I think whatever boardset someone started with, they are likely to recommend because they all seem fairly similar and few issues so far with any.. Cobrapin def. has a good price point, but the limitation is that if you need additional drivers or switches you need to buy another cobrapin board which I believe is more expensive than adding a multimorphic or FAST specific switch/driver board.
FAST <--> Multimorphic .. there's some cost difference depending on how many LEDs, drivers, and switches you want. With FAST - the LEDS are all serial, so if one starts to flake out it tends to affect others down the line. Multimorphic allows a hybrid LED system so some can be parallel and some in series.. but I believe you have to buy driver boards for them whereas FAST has 256 channels built into the main NANO board. I personally went FAST and am very happy with the system.
Sounds like a wide body could work for you. If you can find the Doom custom pinball on youtube, check that out. (It might only be on a thread here, not positive).. that's one of the few very detailed wide bodies I've seen done homebrew. I could see it being similar to what you might want.. swap the theme and graphics and such, add an upper playfield. Even upper PFs - it's hard to make them fun though.. (see about every game Spooky has done). Course some people love em and some hate em.