OP, as frustrating as it can all be, you probably need to take a slight step back and have a think about things.
4. No attempt to enforce payment of the bounty prior to ship destruction.
This doesn't actually make any sense. A bounty is money that's being offered as a reward for your death. In what way could there be an attempt to enforce payment of the bounty prior to ship destruction? - without your ship's destruction, then no one has done what's needed to claim the bounty.
There seems to be a misconception there that's coming up in other places.
See, that's issue #1: a 200 credit bounty should never ever be reason for ship destruction.
A bounty is
always a reason for ship destruction. That is literally what a bounty is. - it is a faction saying 'we are offering x amount of credits as a reward to anyone who 'kills' such and such a cmdr.'
They outright headshot me without warning while I was coming to pay my due.
If there's a price on your head, you can't just turn up to the faction who put the price on your head and pay them the money - they're not asking for money. They are saying they want you killed, and will pay a certain amount of money to whoever does it.
This is why I'm saying you need to have a step back and think about things - because you seem to be expecting that the game should not treat a bounty as a bounty. 'game treated a bounty as a bounty' is not really a legitimate gripe. The big question really is why did you think a bounty wouldn't be treated as a bounty.
Most of what happened to you really stems from that one point. If you were expecting a bounty to be treated as a bounty, would you still have gone and tried to dock normally at a station where the bounty was valid?
Not sure what's happened to leave you with the misconception about the nature of bounties. As far as I can recall (and have been able to double check) bounties have always been bounties, so this isn't something to do with something that had changed while you were away from the game.
As for the loss of all the exploration data - well... what made you think doing other stuff before going and handing in the exploration data was a good idea? The more you do before handing it in, the more risk you have of losing it. It's always been thus, and always will (barring a change by FD so that exploration data survives death).
If you don't want the same thing to happen again, then the best thing you can do is look at it all, understand what it was you did personally that contributed to the situation, and work out what you could do differently in future.
Plenty of salient advice from other cmdrs already to help you with that. Best of luck!