1) Are you trying to argue that if he saves against the Suggestion effect he is immune for 24 hours? Because it only says that about the Fascinate part. It's arguable, but technically the Bard can continue the Fascinate and Suggest at will until it works. Over and over.
I'm just saying that you don't automatically become Suggestion fodder when Fascinated. The Bard has to overcome your considerable will save. And as for doing to over and over, he can only do it for as long as he can perform. I'm just going to say that people can't really perform all day, and if the DM rules that the bard can, that's blatant favoritism.
I'd agree with you there, but I'm just trying to give a heads up to Chuck here. When I hear "I'll totally stomp your Druid with my Core Bard" this is the kind of junk I'm expecting.
2) Ah, well shucks. I had thought asking them to do something obviously harmful just gave them a bonus to their saving throw. But still, with an infinite number of Suggestions and some creative thinking even "reasonable" suggestions are going to eventually kill the Druid. The PHB even gives an example of very lethal type of suggestion that is "legit" - telling them to take a refreshing dip in a pool of acid.
1d6 damage, breaks effect.
Very arguable, and pretty much up to the DM. The spell says "asking" them to do something obviously harmful breaks it. It makes no mention of it breaking the effect if they
are harmed as a result of a "reasonable" suggestion that they succumb to. However, depending on the nature of the suggestion it might end up granting them an extra save against the Fascinate effect, however it isn't likely to succeed and even if it does, that's the end of the Druid's turn and the Bard just has to spend one more Bardic Music to begin again (and he's got a whole lot of these).