Just curious, if Marianne doesn't get the Democratic nomination do you still plan on voting for the Democratic nominee?
Regardless of your feelings about Harris, (I have similar feelings) you must recognize that having her as president would be, by far, the lesser evil when compared to Trump especially if you're concerned about excessive imprisonment / decriminalization of marijuana.
Agree with this. I think tactfully pointing out minor issues you see can be helpful because the implementor is closer to the problem and may have just overlooked the issue and can come up with a solution easily. I've been on the giving and receiving end of this, and so long as everyone is behaving professionally, it's always been helpful.
On the "tactful" note, I'll generally say something like: "I don't have a solution, but I see problem. I don't know that this is reason enough to hold up this PR. I'll leave it up to you."