@Metalize thanks for sparking this awesome discussion and sharing your experiences!
I am, as SNB says, happy to offer my thoughts on Black in general, Black specifically against Purple, and of course, the nightmare that is Blue vs Black.
I contend that Bluecoat is not as useful as you claim, and invite you to show me a specific matchup (via a fixed opening vs it) where it earns its place. I will be happy to be shown mistaken 
I also invite you to show me this P1T1 Blue vs Black opening you feel gets Blue a decently high win rate. I have a pretty long resume of blue vs black games, and I think even if an expert player were to fix Blue’s first three turns of draws, one could not best a 2-8 record against an expert black player drawing randomly (that’s gut feel number, I’d love to see it proven wrong)
As for “does Blue starter need changes”, I still feel strongly that changing Lawful Search to an upgrade (instead of a spell) which could be sacrificed, at any time, for its same effect, is a worthwhile buff to explore. If the flavoring seems off on it with that change, I think you could rename it “Search Warrant” with the same art to make it more “noun-y” and it would be a small buff that would
- Offer Blue some deck-thinning (it could really use it in general, similar to how White can use Safe Attacking)
- Specifically aid Blue in counter-playing Black’s early tempo by utilizing perfect information without risking giving up a hero kill
- Not be a very significant buff in Blue’s other mono matchups
- Make Blue starter more attractive in a multi-color deck
I’m definitely not on board with giving Newsman an ability to block buildings, as I don’t see that as a necessary buff. Newsie is pretty good where he is, if I would suggest any buff to him it would be allowing him to pay gold (1 or 2) to change his number.
I agree 100% with GatG and Constable changes.
Jurisdiction I’ve always felt should cost 1g, but I would be a little worried about what that could do in some multi-color decks.
TL:DR; I love this discussion, let’s throw down some gauntlets, make some bold predictions, and check some stuff out!