Coin tokens work exactly like I predicted. (well, except you can't spend them during your action phase).
The setup effect of this is pretty cool. And there we were thinking that Hinterlands messed with the opening turns.
I think the coin you get at the beginning will be very useful for opening 3/5, which will make for pretty awesome stuff. Could be pretty bad if one player gets to open 2/6 with Goons on the board though, but i think that's the only case where it increases swinginess. Also it will probably help emptying the supply on turn 3, especially if there's another opening modifying effect in this expansion.
The card itself didn't seem that strong to me on first sight, but then i realized it's not a nonterminal copper, but a cantrip copper. WTF that's better than Peddler (not strictly though, Black Market edge case here^^). And wasn't the consensus that that would be a $4 i f it wasn't to boring. Then I realized it doesn't cost $3 as I had thought at first, but $5. That's the right prize point I think. It's not that good then. a $5 peddler where you can save the coin for later. I think the really useful thing about those coin tokens is not that you stockpile them to save up for a big purchase, but rather that it works a bit like the putting back from courtyard (which actually makes it stronger than smithy in some cases). It allows you to distribute money better around turns. Instead of having $7 twice, you can have one $6 and one $8 turn. I like this