Money smoothing is pretty strong; see how Courtyard-BM is better than Smithy-BM. It doesn't smooth out as much as Courtyard, and it relies on having the actions to play Baker, but overall it seems pretty strong.
Should be okay in BM, since in Big Money the key breakpoints are $3, $6, and $8. So, odds are you'll have 1 or 2 coin tokens lying around to jump up to the next breakpoint. Not sure how it works in engines. I want to say it'll be good, but the key point of any engine is that it lets you scale in consistency and buying power at the same time. In order to do that, you'll need all the money you can early on to buy more engine parts. The more buys you have, the more money you can spend each turn, so you'll never have a big store of coin tokens. I think coin tokens will only be useful once the engine is pretty consistent.
As for a coin token fueled mega-turn, it's probably not too likely. If you can draw your deck every turn, you can store +$1 each turn per Baker, or you could buy a Silver instead of a Baker for $2 each turn since you draw the Silver every turn anyways. So, you're storing ~half the money you could have each turn, which sounds a bit too slow.