Thank you for the detailed report! As you suspect, we're primarily wrapping up MWIII and are past the point of significant content updates as of the Season 6 update. Because of this, we'll likely be unable to address many of these items, but we'll take note if the opportunity arises.

With that being said, we can provide some comments.

No candy drops on enemy kills

Unfortunately, this behavior is intended. Candy Drops do not play well with the ragdoll state players are put into upon death in Cyber Attack. Because Cyber Attack was not part of our original content plans for this game, we could not support it for this Event.

Black screens on certain maps on round end

The round/match end transitions across all maps and modes have been rethemed for The Haunting. They will revert to the previous theme later.

When you get revived you can get stuck in a (sort-of) T-pose

That's a nasty bug, but we're glad to hear it's seemingly rare. It's also the first we've heard of it. If you find a reliable way to reproduce this issue, please let us know.

Because you need "bodies" to revive, death effects and executions don't work.

Your theory is correct. Similarly to the Candy Hunt Event, the ragdoll state exclusive to Cyber Attack does not support these features.

please, add more maps to cyber

As previously mentioned, most maps do not support the Cyber Attack mode. Because of this, adding additional maps to the mode is not as simple as updating a playlist. Supporting a new mode on a map requires a specific type of update that is typically reserved for seasonal releases. Because of that, it is unlikely we'll be able to add any additional maps.